1984 AC Custom Cruise III System s Servie Manual Foreword AC Spark Plug Division, General Motors Corporation has prepared this servie manual to help answer questions about operation and servie of the 1984 AC Custom Cruise III ruise ontrol system. This system is offered in two versions, AC Custom Cruise III and AC Integrated Custom Cruise III. It is also referred to as Tri-mode, 3-Mode Cruise or the K-34 Cruise Option. AC Custom Cruise III was introdued on 1983 Chevrolet and GMC truks. All 1984 appliations, exept full-size Cadilla use the AC Custom III system. The Integrated Custom Cruise III system is used on 1984 Corvette and the Pontia Fiero P ar. Custom Cruise III has eletroni iruitry inorporated in a ontroller whih is loated under the dash. The speed signal is derived from the Vehile Speed Sensor (VSS) speedometer buffer amplifier or a permanent magnet (PM) generator. Integrated Custom Cruise III has the eletroni iruitry inorporated in the instrument luster. The speed signal is obtained from a VSS, vehile speed sensor speedometer and/or a transmission driven permanent magnet (PM) generator. Although the 1984 ruise funtion operates similarly in all appliations, there are system design differenes whih are explained in this servie manual. This servie manual is intended to be a quik, easy-to-use referene for serviing the 1984 Custom Cruise III system. It has been organized into four major setions... 1. HOW TO USE CUSTOM CRUISE III 2. COMPONENTS IN THE SYSTEM 3. HOW THE SYSTEM OPERATES 4. DIAGNOSTIC PROCEDURES Im portant Safety Notie To redue the hane of personal injury and/or property damage, the following instrutions must be arefully observed: Proper servie and repair are important to the safety of the servie tehniian and the safe, reliable operation of all motor vehiles. If part replaement is neessary, the part must be replaed with one of the same part number or with an equivalent part. Do not use a replaement part of lesser quality. The servie proedures reommended and desribed in this servie manual are effetive methods of performing servie and repair. Some of these proedures require the use of tools speially designed for the purpose. Aordingly, anyone who intends to use a replaement part, servie proedure or tool, whih is not reommended by the vehile manufaturer, must first determine that neither his safety or safe operation of the vehile will be jeopardized by the replaement part, servie proedure or tool seleted. It is important to note that this manual ontains various autions and noties that must be arefully observed in order to redue the risk of personal injury during servie or repair, or the possibility that improper servie or repair may damage the vehile or render it unsafe. It is also important to understand that these autions and noties are not exhaustive, beause it is impossible to warn of all the possible hazardous onsequenes that might result from failure to follow these instrutions.
Table of Contents Page 1. How to Use Custom Cruise I I I... 1-1 Introdution... 1-1 Operation, 1984 Vehiles... 1-2 Mode Control, Turn Signal Lever Tap-up, Tap-down Feature... 1-2 Mode Control, 1984 Chevrolet Berlinetta... 1-3 2. Components in the S ystem... 2-1 Component Funtions... 2-1 Mode Control Swithes... 2-1 VSS Buffer Amplifier... 2-2 PM Generator Speed Sensor... 2-2 Eletroni Control M odule...2-2 Combination Vauum Release Valve/Converter Cluth Sw ith... 2-3 Vauum Release Valve... 2-3 Combination Vauum Release Swith... 2-3 Eletri Vauum Release Valve... 2-4 Combination Cruise/Stop Light Swith...2-4 Cluth Sw ith...2-4 Servo U n it...2-5 Vauum Aumulator...2-6 Harness Adapter....2-6 3. How the System Operates...3-1 Eletrial/Vauum System Operation... 3-1 System Configurations...3-2 Ciruit Shematis...3-3 4. Diagnosti Proedures...4-1 Preliminary Inspetion...4-1 Test Proedures... 4-2 Cruise System Inoperative... 4-2 Appliable to 1984 Corvette Only... 4-5 Performane Symptoms and Corretion, (All Cruise Systems)... 4-7 Custom Cruise III Quik Cheker... 4-8 Quik Cheker Test Proedure... 4-9 L i s t o f I l l u s t r a t i o n s Figure No. Page 1-1 Mode Control Swithes on Turn Signal Lever. 1-1 1-2 Mode Control, 1984 Chevrolet Berlinetta... 1-1 1-3 Eletroni Cruise Control Operation, 1984 Chevrolet Berlinetta... 1-3 2-1 Mode Control Swithes.2-1 2-2 VSS Buffer Amplifier.2-2 2-3 Speed Sensor.2-2 2-4 Eletroni Controller Module...2-2 2-5 Combination Vauum Release Valve/Converter Cluth Sw ith...2-3 2-6 Vauum Release Valve... 2-3 2-7 Combination Vauum Release Swith, Pontia Fiero... 2-3 2-8 Eletri Vauum Release Valve, Pontia Fiero... 2-4 2-9 Combination Cruise Stop Light Swith... 2-4 2-10 Typial Cluth Sw ith... 2-4 2-11 Servo Unit and Operating Eletro-Mehanism. 2-5 2-12 Typial Pneumati System inluding Vauum Aumulator, Chek Valve and Related Hoses... 2-6 2-13 Harness Adapter...2-6 3-1 Blok Diagram, AC Custom Cruise III System. 3-1 3-2 Blok Diagram, AC Custom Cruise III System with Buffer Amplifier and PM Generator... 3-1 3-3 Typial Installation, AC Custom Cruise III System, K-34 Appliation... 3-2 3-4 Typial Installation, Integrated Custom Cruise III System... 3-3 3-5 1984 Custom Cruise III System Shemati, Optial Speed Sensor Buffer Assembly Identifies Vehile Appliations... 3-5 3-6 1984 AC Custom Cruise III System Shemati A and C Cars, Speed Sensor PM Generator Identifies Other Vehile Appliations... 3-7 3-7 AC Integrated Custom Cruise III System, Shemati, 1984 Corvette... 3-9 3-8 AC Custom Cruise III System Shemati, 1984 Pontia Fiero P Car... 3-11 4-1 Servo Resistane Measurement... 4-2 4-2 Speedometer Signal Generator J-33431... 4-6 4-3 Quik Cheker Model No. ET-3475... 4-8 4-4 Quik Cheker Model No. J-34185... 4-8 4-5 Quik Cheker Model No. QC111... 4-9 4-6 Optional Adapter (QC31) for Pontia Fiero P Car... 4-9
1. How to Use Custom Cruise III Introdution The 1984 AC Custom Cruise III system is an extension of the ruise ontrol system that AC Spark Plug Division has designed and produed sine the 1977 vehile model year. The Custom Cruise III system has been adapted to aommodate the lower manifold vauum levels of smaller, fuel effiient vehiles. AC Custom Cruise III plaes at the driver s ommand the ruise ontrol funtions of ruise, oast, resume speed, tapup, tap-down and aelerate. All funtions, exept for 1984 Chevrolet Berlinetta, are built-in the turn-signal lever (figure 1-1). The 1984 Chevrolet Berlinetta has ruise ontrol funtions built in the steering wheel T spoke.. the ON- OFF swith is on the floor onsole (figure1-2). Figure 1-1, Mode Control Swithes on Turn Signal Lever. RESUME COAST ACCELERATE ON-OFF... ROCKER SWITCH ON FLOOR CONSOLE Figure 1-2, Mode Control, 1984 Chevrolet Berlinetta. 1-1
DO NOT HOLD THE SLIDER IN THE R/A POSITION... RELEASE IT IMMEDIATELY. 1. How to Use Custom Cruise III -------------- Operation, 1984 Vehiles C Mode Control on Turn Signal Lever To engage the ruise mode, the slide lever must be moved from the off to the on position and the set push button (loated in the end of the turn signal lever) must be depressed and released. The ruise set speed will be the vehile speed at the partiular time when the set push button is released. However, there is no ruise engagement below 25 mph. This is a low speed inhibit feature. The system may be disengaged by moving the mode ontrol swith to the off position or by depressing the vehile brake pedal or luth pedal on manual transmission vehiles. If the brake pedal is momentarily depressed to disengage ruise operation, the ruise set speed will be retained in the system memory. To return the vehile to the previously set ruise speed, MOMENTARILY move the slider to the R/A (Resume/Ael) position. If the slider is held in the R/A position for more than one seond, the system reverts to the ACCEL mode. When the slider is released, the speed the vehile aelerated to beomes the new ruise speed. The vehile operator may erroneously interpret this as an inoperative resume funtion. The vehile will automatially aelerate to the previously set speed at a ontrolled rate. The ontroller remembers the last ruise speed unless leared by an on-off of the ignition swith or the slider swith on the turn signal lever. If the slider is moved to the R/A position while in ruise and held, the vehile will aelerate at a ontrolled rate until the slider is released. When the slider is released, the vehile will ontinue to ruise at that speed. Reduing set speed an be aomplished by depressing and holding the SET/COAST button on the end of the turn signal lever until the vehile oasts down to the desired speed. Vehile speed at the moment of SET/COAST button release is the new set ruise speed. The aelerate funtion an be operated in either the ruise or non-ruise modes. Momentary slider swith movement to the R/A position after an on-off yle will appear as a set ruise speed funtion. Tap-up, Tap-down Feature On all 1984 appliations, exept Corvette and Pontia Fiero P ar, the Custom Cruise III system has a tap-up, tapdown speed adjustment feature. Tap-up results in a one-mile per hour speed inrease by merely tapping the RESUME/ACCEL slider for less than one seond. Tap-up may be repeated, but speed inrease is limited to 10 miles per hour above vehile speed. Tap-down results in a one-mile per hour speed derease by merely tapping the SET/COAST button for less than 0.4 of a seond. Eah tap dereases speed and may be aumulated... it is limited to a minimum ruising speed of 25 miles per hour. NOTE If both the SET/COAST and R/A slider are operated at the same time, ruise beomes inoperative and the system memory is erased. 1-2
1. How to Use Custom Cruise III Mode Control, 1984 Chevrolet Berlinetta Figure 1-3 desribes operation of the 1984 Chevrolet Berlinetta Eletroni Cruise Control. The aelerator may be depressed at any time to override the ruise system. Release of the aelerator will return the vehile to the previous set ruise speed. STEERING WHEEL CONTROLS ON-OFF Roker swith floor onsole Figure 1-3, Eletroni Cruise Control Operation, 1984 Chevrolet Berlinetta.
2. Components in the System Component Funtions Mode Control Swithes Turn Signal Lever The various operating modes of the Custom Cruise III system are ontrolled by means of the Mode Control Swithes normally loated on the turn signal lever (figure 2-1). Steering Wheel Custom Cruise III operating modes are ontrolled by Mode Control Swithes built-into the steering wheel on 1984 Chevrolet Berlinetta (figure 2-1)... ON-OFF is a roker swith on the floor onsole. 2-1
2. Components in the System VSS Buffer Amplifier Vehile speed information is transmitted to the Eletroni Controller by a speed sensor, (a Vehile Speed Sensor (VSS) Buffer Amplifier). See figure 2-2. The output of the VSS Buffer Amplifier is a frequeny proportional to vehile speed. The signal is a square wave with a frequeny of 0.556 Hz/MPH. PM Generator Speed Sensor The PM generator speed sensor (figure 2-3) generates vehile speed information in the form of a sine wave with a frequeny of 1.112 Hz/MPH. On Integrated Custom Cruise III, this signal is fed diretly to the instrument luster where it is onverted to 0.556 Hz/MPH for ruise usage. On Custom Cruise III K34 option, it is fed to a buffer amplifier, where it is onverted to 0.556 Hz/MPH for ruise usage. Figure 2-3, PM Generator Speed Sensor. Eletroni Control Module The Eletroni Controller (figure 2-4) ontains a digital integrated iruit and supporting analog iruits. The ontroller interprets the position of the servo unit, the position of the mode ontrol swithes and the output of the speed sensor. In response to these inputs, the ontroller eletrially signals the opening or losing of the vent and vauum solenoid valves in the servo unit (see figure 2-11). In Custom Cruise III appliations, the Eletroni Controller shown in figure 2-4 is usually mounted on some strutural omponent under the dash. On Integrated Custom Cruise III, introdued on 1984 Corvette, and Pontia Fiero P ar, the eletroni iruitry is built-in the instrument panel. Q 2-2
2. Components in the System Combination Vauum Release Valve/ Converter Cluth Swith Vehiles equipped with a lok-up torque onverter (loking luth) transmission use a Combination Vauum Release Valve/Converter Cluth Swith (figure 2-5). The Vauum Release Valve provides an additional vent for the servo unit to the atmosphere when the brake pedal is held in a depressed position. This venting ation is spring atuated when the brake pedal is depressed and ours within the free-travel of the brake pedal arm. At the same time, the ontats in the Converter Cluth Swith open, whih disengages the loking luth mehanism in the transmission. Valve/Converter Cluth Swith. Vauum Release Valve C Vehiles without a lok-up torque onverter luth transmission use a Vauum Release Valve (figure 2-6). It provides an additional vent for the servo unit to the atmosphere when the brake pedal is held in a depressed position. This venting ation is spring atuated when the brake pedal is depressed and ours within the free-travel of the brake pedal arm. Figure 2-6, Vauum Release Valve. C Combination Vauum Release Swith C A ombination vauum release swith is loated in the brake pedal braket in the Pontia Fiero P ar (figure 2-7). When the brake is applied, the vauum release swith de-energizes an eletri vauum release valve (see figure 2-8). Figure 2-7 shows a brake pedal operated ombination vauum release/torque onverter luth swith used with automati transmissions. On manual transmission ars, a similar swith arrangement is used on the brake and luth pedal brakets. VACUUM RELEASE LARGE BARREL TORQUE CONVERTER CLUTCH Figure 2-7, Combination Vauum Release Swith, Pontia Fiero. 2-3
2. Components in the System Eletri Vauum Release Valve The eletri vauum release valve is used in the 1984 Pontia Fiero P ar (figure 2-8). The solenoid in the valve is powered by vehile ignition. When the brake pedal is NOT depressed, the solenoid is energized and the vauum valve is losed. When the brake is applied, the solenoid de-energizes and the vauum valve and servo vent to the atmosphere... the ruise funtion disengages. (See Vauum Release Swith, Figure 2-7). 4 Combination Cruise/Stop Light Swith The Combination Cruise/Stop Light Swith (figure 2-9) is used with a separately mounted vauum release valve. When the brake pedal is depressed, the swith illuminates the stop lights and disengages the ruise. One set of eletrial ontats operate the stop light... the other set operates the ruise disengage funtion. Figure 2-9, Combination Cruise/Stop Light Swith. Cluth Swith On vehiles with manual transmissions, an eletri Cluth Swith (figure 2-10) is used. Depressing the luth for up or downshifting a manual transmission disengages the ruise funtion. The ruise funtion remains disengaged after the luth pedal is released ) Figure 2-10, Typial Cluth Swith. 2-4
2. Components in the System r ----------------------- Servo Unit f The Servo (figure 2-11) onsists of a vauum operated diaphragm, a normally open solenoid valve to vent the diaphragm hamber to atmosphere, a normally losed solenoid valve to onnet the diaphragm hamber to the vauum soure, and a variable indutane position sensor. The servo operates the throttle in response to signals from the eletroni ontroller as follows: Steady State Cruise Funtion Both vauum and vent valves are losed or sealed. The servo has a onstant vauum on the diaphragm and plaes no-flow requirements on the vauum soure. Vehile Losing Speed The ontroller energizes the vauum solenoid to open the vauum valve to the vauum soure. This inreases the vauum level in the servo to inrease the throttle angle... the vent valve remains losed. Vehile Gaining Speed The ontroller de-energizes the vent solenoid to open the vent valve to the atmosphere whih redues vauum in the servo and allows the throttle return spring to derease the throttle angle... the vauum valve remains losed. VACUUM SOLENOID AND VALVE (NORMALLY CLOSED) C THROTTLE ATTACHMENT VARIABLE INDUCTANCE POSITION SENSOR VACUUM SUPPLY PORT (TO VACUUM SUPPLY) VACUUM RELEASE PORT (TO VACUUM BRAKE RELEASE VALVE) INTERNAL VIEW VENT SOLENOID AND VALVE (NORMALLY OPEN) Figure 2-11, Servo Unit and Operating Eletro-Mehanism. 2-5
2. Components in the System Vauum Aumulator For aeptable ruise performane in vehiles with low manifold vauum at road load, a Vauum Aumulator (figure 2-12) is used. The Aumulator is attahed to the intake manifold through a hek valve and stores the high vauum level that is available during periods of low engine loading. The system operates on aumulator vauum, when higher than manifold vauum. The Vauum Aumulator or hek valve is not used with diesel engines. ACCUMULATOR Figure 2-12, Typial Pneumati System inluding Vauum Aumulator, Chek Valve and Related Hoses. Some systems use a 3-port hek valve instead of a 2-port valve. ) Harness Adapter The Harness Adapter (figure 2-13) is used on some Custom Cruise III appliations to onnet the Harness Assembly to the Servo Unit. 0 rigure 2-13, Harness Adapter. 2-6
3. How the System Operates t------------------------------ Eletrial/Vauum System Operation Figure 3-1 is a blok diagram illustrating omponent relationships in the AC Custom Cruise III system. The servo vent solenoid valve and servo vauum solenoid valve ontrol the vauum level in the servo in response to information from the eletroni ontroller. The servo, in turn, ontrols the throttle position. The eletroni ontroller reeives input signals from the mode ontrol swithes, brake release swith, speedometer buffer amplifier and a feedbak signal from the servo position sensor. C C Figure 3-1, Blok Diagram, AC Custom Cruise III System. Figure 3-2 shows the same blok diagram (as figure 3-1) exept that the speed sensor is a PM generator whih supplies a speed signal of 1.112 Hz per MPH to a buffer amplifier. The buffer in turn divides the signal by two to provide a frequeny of 0.556 Hz per MPH to the eletroni ontrol module for ruise operation. Figure 3-2, Blok Diagram, AC Custom Cruise III System with Buffer Amplifier and PM Generator. 3-1
3. How the System Operates System Configurations Figure 3-3 shows a typial AC Custom Cruise III (K-34) system installation. d o VACUUM FITTING VACUUM CHECK VALVE SERVO VACUUM ACCUMULATOR HARNESS ADAPTER SPEED SENSOR SPEEDO-CABLE ELECTRONIC CONTROLLER BRAKE PEDAL BRACKET ) O l/p HARNESS FUSE PANEL CLUTCH ELECTRIC SWITCH BRAKE PEDAL BRACKET v VACUUM RELEASE VALVE HARNESS SWITCH CLUTCH PEDAL BRAKE PEDAL STOP LP SW BRAKE PEDAL CONNECTOR ACTUATOR BRKT o Figure 3-3, Typial Installation, AC Custom Cruise III System, K-34 Appliation. 3-2
3. How the System Operates 0 Figure 3-4 illustrates a typial AC Integrated Custom Cruise III System installation. Note that the eletroni iruitry is loated in the instrument display. The speed sensor, a PM Generator, is driven by the transmission. ACCELERATOR BRACKET CONNECTOR TO ELECTRONIC CONTROLLER IN INSTRUMENT DISPLAY WIRING HARNESS INSTRUMENT DISPLAY TO CONTROLLER WIRING HARNESS C CRUISE CONTROL CABLE SERVO ASSEMBLY WIRING HARNESS VACUUM HOSE / PM GENERATOR VACUUM RELEASE VALVES & SWITCHES STOP LAMP SWITCH & BRACKET VACUUM ACCUMULATOR TO ELECTRONIC CONTROLLER TRANSMISSION Figure 3-4, Typial Installation. Integrated Custom Cruise III System. Ciruit Shematis The AC Custom Cruise III iruit shemati shown in figure 3-5 applies to all 1984 model A, F, J and X ars exept Buik and Oldsmobile J ars and the Berlinetta F ar. Figure 3-6 is the iruit shemati for 1984 model A and C ars... figure 3-7 is the 1984 Corvette shemati... figure 3-8 is for the 1984 Pontia Fiero P ar. C 3-3
3. How the System Operates NOTE All shemati drawings have onnetor voltage and resistane valves shown to aid in iruit traing and eletrial testing. Refer to figure 3-5 and figure 3-6... When the ignition swith is ON, battery voltage is applied to the Mode Control Swith and Buffer Amplifiers. When the slider swith is in the ON position, battery voltage is applied to terminal A of the Control Module Connetor. If the brake and/or luth are not applied, battery voltage is present at terminal G. When the R/A, Resume/Ael slider is in the ON position, battery voltage is applied to terminal M. When the SET/COAST button is depressed, battery voltage is applied to terminal L. The ontroller sends a vent valve signal, it flows from terminal C to terminal A at the servo unit, then through the servo vent oil to servo terminal C, then to Cruise Ground at the I.P., instrument panel. NOTE On some 1984 vehiles, the ruise ground is loated under the hood. Servo terminals B and D omplete the SPS, servo position iruit. The servo position iruit originates at terminal F, ontrol module onnetor, flows through servo terminal B, through the SPS oil to servo terminal D, then to terminal H at the ontrol module onnetor. The ontroller sends a vauum valve signal whih originates at terminal K and flows to servo terminal E, through the servo vauum oil to servo terminal C, then to ontrol module onnetor terminal J... ruise ground at the I.P., instrument panel. A Cruise Lamp is used on some 1984 appliations. The ontrol module onnetor terminal B (figure 3-6) is used to ground the ruise lamp. Control module onnetor terminal J is Cruise Ground. On 1984 Corvette (figure 3-7) Cruise Ground is on terminal D-3. On Pontia Fiero P ar (figure 3-8), Cruise Ground is on ontroller terminal P Control module onnetor terminal D (figure 3-5) is the speed sender terminal. In operation, voltage will osillate between a high of 4 to 12 volts and a low of near ground, depending on other uses of this signal. Control module onnetor terminal E is intended for an optional TCC signal (figures 3-5 and 3-6). The C ar iruit shown in figure 3-6 is very similar to the iruit shown in figure 3-5. 1. Terminal identifiation at the ontroller is identified by name... i.e. BRAKE, CRUISE ON-OFF, et. 2. The Buffer Amplifier, loated between the PM Generator and Control Module Connetor has a variable signal output... 1.112 Hz for the speedo speed signal, 0.556 Hz for the ruise signal. 3-4
3. How the System Operates 3. How the System Operates < VOLTAGE CHECK MODULE CONNECTED TEST TERMINAL FUNCTION SPECIFIED VOLTAGE TO GROUND CONDITIONS Vi G BRAKE INPUT 12V... OV... BRAKE/CLUTCH NOT APPLIED BRAKE/CLUTCH APPLIED P E D CONN 1 2 0 3 4 1 2 5 v 2 A CRUISE ON-OFF INPUT 12V... OV... SLIDER SWITCH ON SLIDER SWITCH OFF, SET/COAST DEPRESSED OR NORMAL v 3 M RESUME/ACCEL INPUT 12V... OV... SLIDER SWITCH IN R/A POSITION SLIDER SWITCH ON, SET/COAST DEPRESSED OR NORMAL OV... SLIDER SWITCH OFF, SET/COAST DEPRESSED OR NORMAL SET/COAST 12V... SLIDER SWITCH ON, SET/COAST DEPRESSED v 4 L INPUT OV... OV... SLIDER SWITCH ON, SET/COAST NORMAL SLIDER SWITCH OFF, SET/COAST NORMAL v 5 B CRUISE LAMP 12V... CRUISE ENGAGED v 6 D SPEED SIGNAL GREATER THAN 4V HIGH, NEAR OV LOW DRIVE WHEELS ROTATING ON APPLICATIONS LISTED, FIGURE 3-5 RESISTANCE CHECK MODULE DISCONNECTED I f V TEST TERMINAL FUNCTION Ri r2 Fb CTO GROUND FTOH F TO GROUND H TO GROUND KTO GROUND VENT VALVE CONTROL SPS HIGH, SPS LOW VACUUM VALVE CONTROL SPECIFIED RESISTANCE 30-550... OPEN CIRCUIT... 15-250... OPEN CIRCUIT... 30-550... OPEN CIRCUIT... CONDITIONS MEASURED TO GROUND, SERVO CONNECTED MEASURED TO GROUND, SERVO DISCONNECTED MEASURED F TO H, SERVO CONNECTED MEASURED F AND H TO GROUND, SERVO DISCONNECTED MEASURED TO GROUND, SERVO CONNECTED MEASURED TO GROUND, SERVO DISCONNECTED OPTICAL SPEED SENSOR/BUFFER ASM ALL 84 EXCEPT Y, "X" A, F" B O J 25007421 (15 INCH) 25007462 (26 INCH) 25007463 (32 INCH) P E D CONN 1 2 0 1 5 6 8 6 IGN 1 GND SPEED SIGNAL (C3I P E D CONN 1 20 3 4 1 1 7 SPEED SIGNAL (CRUISE) CUSTOM CRUISE III INSTALLATION DIAGRAM (EXCEPT 84C, 84Y, 84P CAR AND CHEVROLET BERUNETTA) NOTE: REFER TO CHEVROLET SERVICE MANUAL FOR BERUNETTA FU J TO GROUND GROUND on... MEASURED TO VEHICLE GROUND Figure 3-5, 1984 Custom Cruise III System Shemati Optial Speed Sensor Buffer Assembly Identifies Vehile Appliations. 3-5 3-6
3. How the System Operates 3. How the System Operates > P E D. CONN 1 2 0 3 4 1 2 5 G A BRAKE CRUISE ON/OFF CLUTCH SWITCH (OPTIONAL) - o 1> P.E D. CONN. 1 2020651.OCK PART NO. NORMALLY OPEN CRUISE MODE CONTROL ENGAGE SWITCH 2 50 3 1 4 5 6 (DELAY WIPER) 2 5 0 3 1 4 5 7 (2 -SPEED WIPER) TEST TERMINAL FUNCTION Vi G VOLTAGE CHECK MODULE CONNECTED SPECIFIED VOLTAGE TO GROUND BRAKE INPUT 12V... OV... CONDITIONS BRAKE/CLUTCH NOT APPLIED BRAKE/CLUTCH APPLIED CONTROL MODULE CONNECTOR S b r - * - (5) - (5> M L C F H K J E D B IGN >------- (J )------» - RESUME/EXCEL. SET/COAST VENT. VALVE SPS HI SPS LO VACUUM VALVE CRUISE GND TCC MOD. SPEED SENSOR CRUISE LAMP AT INSTRUMENT PANEL V2 V3 V4 A M L CRUISE ON-OFF INPUT RESUME/ACCEL INPUT SET/COAST INPUT 12V... OV... 12V... OV... OV... 12V... OV... OV... SLIDER SWITCH ON SLIDER SWITCH OFF, SET/COAST DEPRESSED OR NORMAL SLIDER SWITCH IN R/A POSITION SLIDER SWITCH ON, SET/COAST DEPRESSED OR NORMAL SLIDER SWITCH OFF, SET/COAST DEPRESSED OR NORMAL SLIDER SWITCH ON, SET/COAST DEPRESSED SLIDER SWITCH ON, SET/COAST NORMAL SLIDER SWITCH OFF, SET/COAST NORMAL BUFFER ASM PART NO. 2 5 0 0 9 9 1 4 P.E D. CONN 8 9 1 7 7 6 7 SPEEDO SPD SIG B/C AUX SPD SIG {1.11 2 HZ/MPH) CRUISE SPD SIG (.556 HZ/MPH) C3 SPD SIG (.556 HZ/MPH)v 3 POWER GROUND IS V SW IGN SPEED SENSOR HI SPEED SENSOR LO P.E D. CONN 1 2 0 2 0 6 4 6 VENT VALVE Vs v6 D B SPEED SENSOR GREATER THAN 4V HIGH, NEAR OV LOW DRIVE WHEELS ROTATING CRUISE LAMP 12V... CRUISE ENGAGED RESISTANCE CHECK MODULE DISCONNECTED P.E D. CONN 2 9 8 9 9 1 4 B/C SPEED SENSOR (PM GENERATOR) A AND C AUTO. TRANS. 25007335 CUSTOM CRUISE III INSTALLATION DIAGRAM 1984 A AND C CARS TEST TERMINAL FUNCTION Ri C to GROUND F TO H VENT VALVE CONTROL SPS HIGH, SPECIFIED RESISTANCE 30-550... OPEN CIRCUIT... 15-250... CONDITIONS MEASURED TO GROUND, SERVO CONNECTED MEASURED TO GROUND, SERVO DISCONNECTED MEASURED F TO H, SERVO CONNECTED OTHER APPLICATIONS "P " AUTO TRANS. 2 5 0 0 7 3 3 5 MAN. TRANS. 2 5 0 0 7 3 3 6 " Y ALL 2 5 0 0 7 3 3 9 or 2 5 0 0 7 3 3 8 "F " AUTO.TRANS. 2 5 0 0 7 3 3 8 MAN TRAN 2 5007350 r 2 F TO GROUND H TO GROUND SPS LOW OPEN CIRCUIT... MEASURED F AND H TO GROUND, SERVO DISCONNECTED Fh K to GROUND VACUUM VALVE CONTROL 30-550... OPEN CIRCUIT... MEASURED TO GROUND, SERVO CONNECTED MEASURED TO GROUND, SERVO DISCONNECTED FU J to GROUND GROUND oo... MEASURED TO VEHICLE GROUND Figure 3-6, 1984 Custom Cruise III System Shemati, A and C ars Speed Sensor PM Generator identifies other Vehile Appliations. 3-7 3-8
3. How the System Operates 3. How the System Operates VOLTAGE CHECK AT CLUSTER MODULE CONNECTED TEST TERMINAL FUNCTION SPECIFIED VOLTS TO GROUND CONDITIONS Vi C12 BRAKE INPUT 12V... 0V... BRAKE/CLUTCH NOT APPLIED BRAKE/CLUTCH APPLIED v2 C7 CRUISE ON-OFF 12V... 0V... SLIDER SWITCH ON SLIDER SWITCH OFF, SET/COAST DEPRESSED OR NORMAL v3 C11 RESUME/ACCEL INPUT 12V... 0V... 0V... SLIDER SWITCH IN R/A POSITION SLIDER SWITCH ON, SET/COAST DEPRESSED OR NORMAL SLIDER SWITCH OFF, SET/COAST DEPRESSED OR NORMAL v4 V5 C13 C15 and D11 SET/COAST INPUT SPEED SENSOR INPUT 12V... 0V... 0V... 1.8 to 2.5 VAC (APPROXIMATE) SLIDER SWITCH ON, SET/COAST DEPRESSED SLIDER SWITCH ON, SET/COAST NORMAL SLIDER SWITCH OFF, SET/COAST NORMAL MEASURED BETWEEN A15 AND B11, VEHICLE SPEED 10 MPH V6 SEE SCHEMATIC CLUTCH AND BRAKE INPUT 12V... 0V... BRAKE/CLUTCH NOT APPLIED BRAKE/CLUTCH APPLIED RESISTANCE CHECK MODULE DISCONNECTED TEST TERMINAL FUNCTION SPECIFIED RESISTANCE CONDITIONS ( Ri r2 D8 TO GROUND C10 to C14 VENT VALVE CONTROL SPS HIGH AND SPS LOW 30-55fl... OPEN CIRCUIT.. 15-25H... OPEN CIRCUIT.. MEASURED TO GROUND, SERVO CONNECTED MEASURED TO GROUND, SERVO DISCONNECTED MEASURED BETWEEN C10 and C14; SERVO CONNECTED MEASURED BETWEEN C10 AND GROUND AND C14 AND GROUND, SERVO DISCONNECTED 1984 CORVETTE CUSTOM CRUISE III INSTALLATION DIAGRAM r3 D9 TO GROUND VACUUM VALVE CONTROL 30-55fi... OPEN CIRCUIT.. MEASURED TO GROUND, SERVO CONNECTED MEASURED TO GROUND, SERVO DISCONNECTED ( R4 Rs D3 C15 to D11 CRUISE GROUND on... MEASURED TO VEHICLE GROUND PM GENERATOR CIRCUIT 346 to 493fl MEASURED BETWEEN C15 AND D11 Figure 3-7, AC Integrated Custom Cruise III System Shemati, 1984 Corvette. 3-9 3-10
3. How the System Operates 3. How the System Operates o VOLTAGE CHECK AT CLUSTER MODULE CONNECTED TEST TERMINAL FUNCTION SPECIFIED VOLTS TO GROUND CONDITIONS 9 <S> INSTRUMENT CONNECTOR i BRAKE CRUISE ON/OFF RESUME/ACCEL. SET/COAST VENT VALVE SPSHI SPS LO VACUUM VALVE CRUISE GND. _SPE ED_SENSOR_LO_ SPEED SENSOR HI CLUTCH SWITCH (OPTIONAL) -» olp» - AT INSTRUMENT. PANEL *BRAKE SWITCH A (RADIO FUSE) BRAKE SWITCH D CONNECTOR r B 2 A 4 C 1 n 3 VACUUM RELEASE SOLENOID T 'LOCATED ON BRAKE PEDAL BRACKET NORMALLY OPEN CRUISE FNGAGE SWITCH : ii i 1 \ ON/OFF \ \ / Vi v 2 v 3 V 4 V5 L D G M R and S BRAKE INPUT 12V... OV... CRUISE ON-OFF 12V... OV... RESUME/ACCEL INPUT SET/COAST INPUT SPEED SENSOR INPUT 12V... OV... OV... 12V... OV... OV... 1.8 to 2.5 VAC (APPROXIMATE) BRAKE/CLUTCH NOT APPLIED BRAKE/CLUTCH APPLIED SLIDER SWITCH ON SLIDER SWITCH OFF, SET/COAST DEPRESSED OR NORMAL SLIDER SWITCH IN R/A POSITION SLIDER SWITCH ON, SET/COAST DEPRESSED OR NORMAL SLIDER SWITCH OFF, SET/COAST DEPRESSED OR NORMAL SLIDER SWITCH ON, SET/COAST DEPRESSED SLIDER SWITCH ON, SET/COAST NORMAL SLIDER SWITCH OFF, SET/COAST NORMAL MEASURED BETWEEN R AND S, VEHICLE SPEED 10 MPH D CONNECTOR RESISTANCE CHECK MODULE DISCONNECTED X TEST TERMINAL FUNCTION SPECIFIED RESISTANCE CONDITIONS PM GENERATOR 1984 PONTIAC FIERO P CAR CUSTOM CRUISE III INSTALLATION DIAGRAM Ri r2 N TO GROUND J to E VENT VALVE CONTROL 30-55H... OPEN CIRCUIT.. SPS HIGH and SPS LOW 15-25fi... OPEN CIRCUIT.. MEASURED TO GROUND, SERVO CONNECTED MEASURED TO GROUND, SERVO DISCONNECTED MEASURED BETWEEN J AND E; SERVO CONNECTED MEASURED BETWEEN J AND GROUND AND E AND GROUND, SERVO DISCONNECTED O r3 F TO GROUND VACUUM VALVE CONTROL 30-55H... OPEN CIRCUIT.. MEASURED TO GROUND, SERVO CONNECTED MEASUREDTO GROUND, SERVO DISCONNECTED R 4 P CRUISE GROUND on... MEASURED TO VEHICLE GROUND Rs R to S PM GENERATOR CIRCUIT 346 to 493fi MEASURED BETWEEN R AND S J Figure 3-8, AC Custom Cruise III Shemati, 1984 Pontia Fiero P Car. 3-11 3-12
4. Diagnosti Proedures v Preliminary Inspetion An undesirable ruise ontrol performane symptom an be mehanial, vauum, eletrial or a ombination of the three. In all ases perform a visual inspetion of all omponents in the ruise system. Things to hek are... Disonneted or damaged wiring Pinhed, raked or disonneted vauum hoses Craked or broken vauum fittings at the servo or aumulator Corret positioning of the hek valve in the servo and aumulator vauum line (see figure 2-12). C p ~ -- _-----. NOTE To avoid breaking vauum ports, are must be exerised in removing vauum hoses from fittings. If neessary ut hose. Inspetion Notes C 4-1
4. Diagnosti Proedures ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ^ Test Proedures Cruise System Inoperative The following proedure applies to all Custom Cruise III systems exept 1984 Corvette (for Corvette see page 4-5). Step 1 Perform the voltage and resistane heks for the partiular ruise system installation (see figures 3-5, 3-6 or 3-8 as appropriate). Servo resistane measurement (vent valve ontrol or vauum valve ontrol) an be made at the servo as shown in figure 4-1. SERVO CONNECTOR DISCONNECTED MEASURE AT SERVO PINS <3 PIN FUNCTION RESISTANCE CONDITIONS D to B SPS 15-25 fi MEASURED BETWEEN PINS D AND B (IF MEASURED RESISTANCE IS NOT STATED VALUE, REPLACE SERVO) A to C E to C VENT VALVE VACUUM VALVE 30-55 fi 30-55 f i MEASURED BETWEEN PINS A AND C (IF MEASURED RESISTANCE IS NOT STATED VALUE, REPLACE SERVO) MEASURED BETWEEN PINS E AND C (IF MEASURED RESISTANCE IS NOT STATED VALUE, REPLACE SERVO) Figure 4-1, Servo Resistane Measurement. 4-2
4. Diagnosti Proedures Step 2 Exept for 1984 Pontia Fiero P ar, perform the following vauum heks: NOTE For Pontia Fiero, plug the vauum release port on the servo (figure 2-11) and perform vauum servo tests 1 and 2, test table 4-1. Vauum Servo Tests Perform Preliminary Inspetion (see page 4-1). Disonnet the bead hain, able (or rod) and eletrial onnetor at the servo. Start the engine... or apply vauum to the servo vauum port. Proeed to Test Table 4-1, Vauum Servo Tests. Test Ation Reation 1 Apply 12 volts to A and E, then ground C (A-C loses the normally open vent valve E-C opens the normally losed vauum valve) Servo should full stroke. If not, hek vauum hoses to the vauum supply. 2 Remove voltage from E The servo should hold a full stroke. If not, go to the next step. On Pontia Fiero, replae the servo. If servo holds, go to step 4. 3 Disonnet the vauum brake release at the servo and plug the servo. Momentarily apply 12 volts to E to allow the servo to full stroke. 4 Turn Ignition ON Turn Ignition OFF and disonnet vauum valve onnetor at the valve. Turn Ign. ON If the servo holds its position, adjust the brake vauum release valve or replae the valve. Vauum release valve should engage. With a properly adjusted brake swith, battery voltage should be present aross the (2) onnetor terminals (figures 2-8 and 3-8). No battery voltage indiates an open iruit (see figure 3-8). Test Table 4-1, Vauum Servo Tests. 4-3
4. Diagnosti Proedures ----------------------------- <3 Step 3 Chek eletrial operation of the mode ontrol swithes by replaing the swith with a known good swith, or perform the tests listed in Table 4-2, Mode Control Swith Test. For Chevrolet Berlinetta perform the tests listed in Table 4-3, Mode Control Test, Chevrolet Berlinetta. SET/COAST POSITION 1-2 1-3 1-4 2-3 2-4 3-4 (S/C) SW SLIDER C-B C-D C-A B-D B-A D-A C Closed O Open Normal Off 0 0 0 0 0 0 Normal On 0 0 0 0 o Normal R/A o 0 0 Depressed Off 0 0 0 o 0 Depressed On o o o Depressed R/A TERMINAL B / YELLOW WIRE, BOTTOM, #1 C / / TERMINAL A \ BLUE WIRE, TOP, #4 TERMINAL D" RED WIRE, BOTTOM, #3 Table 4-2, Mode Control Swith Test. 0 4-4
4. Diagnosti Proedures PERFORM WITH IGNITION AND CONSOLE ON-OFF SWITCHES ON Set/Coast Resume/ Aelerator Volts at Cruise Power Volts at Set/Coast Volts at Resume/Aelerator Volts at Brake Swith Normal Normal Battery O 0 * Battery Depressed Normal Battery Battery 0 * Battery Normal Normal Battery 0 0 * Battery Normal Depressed Battery 0 Battery * Battery 'With the onsole swith in the OFF position, O-volts should be indiated. Table 4-3, Mode Control Test, Chevrolet Berlinetta. Appliable to 1984 Corvette Only Step 5 Perform servo eletrial tests desribed in figure 4-1. YELLOW (CRUISE POWER, IGN ON ) Step 1 Refer to shemati, figure 3-7. At test point V6 hek for 12 volts, luth and brake not applied. Step 2 Chek vauum release valve operation (figure 2-6). Step 3 Inspet vauum hose, and fittings for restritions and loose onnetions. Step 4 Make sure eletrial onnetions are not loose or defetive. Step 6 Chek mode ontrol swith per Diagnosti Proedures, step 4, table 4-2. Step 7 Chek servo vauum, per Diagnosti Proedures, step 2, table 4-1. 4-5
4. Diagnosti Proedures Step 8 Use speedometer Signal Generator J-33431 (figure 4-2) to perform the following funtional hek: 8a. Turn off the ignition swith... then disonnet the body harness onnetor from the PM Generator at the transmission. 8b. Disonnet the servo throttle linkage at the servo unit. 8. Connet Speedometer Signal Generator, J-33431, to the PM Generator harness onnetor. Use the onnetors provided with signal generator. 8d. Set the tester to the 54 MPH position. NOTE Speedometer Signal Generator J-33431 features other test apabilities. Use the signal generator only as desribed in Steps 8a, b, and d. Figure 4-2, Speedometer Signal Generator J-33431, 4-6
4. Diagnosti Proedures Step 9 Start the engine... set the Mode Swith Slider to the ON position. Go to Steps 9a, b, and d. Step Ation Reation 9a Depress and release set oast swith (S/C). Servo will pull to approximately 28 to 42% of servo position travel and hold. 9b Move ruise lever slider to Resume /Aelerate (R/A) and hold for 3 seonds. Release slider. Servo will pull to the full stroke travel position and hold. After releasing slider from the R/A position, the servo will return to 28 to 42% of the travel position. 9 Depress brake and/or luth pedal. Servo will move to the losed throttle position. 9d Momentarily move ruise lever slider to Resume/Aelerate (R/A) position. Servo will pull to the 28 to 42% position of travel and hold. Step 10 If the tests performed in steps 9a, b, and d did not meet speifiations, perform vauum servo tests (test table 4-1). If OK remove the luster trim to expose the luster and luster onnetor. 10a Perform voltage and resistane heks by bak probing at the onnetor (see figure 3-7, voltage and resistane speifiations). 10b If no defet is found, replae the luster assembly. Performane Symptoms and Corretion (All Cruise Systems) Cruise System Surges Step 1 Step 2 Step 3 The servo and throttle linkage should operate freely and smoothly. This linkage should be adjusted as desribed by the vehile servie manual. Hoses should be properly routed with no restritions or leaks. Chek the servo as per proedures desribed in figure 4-1, eletrial hek, page 4-2... step 9, eletrial vauum hek, above... and Table 4-1, Vauum Servo Test, page 4-3. Replae the servo if required. If no system defet is noted, replae the eletroni ontroller or liquid rystal display. Cruise Set Speed High or Low Step 1 Step 2 Step 3 Step 4 Chek module for orret part number (see figures 3-5, 3-6, 3-7 or 3-8 as appropriate). Chek servo linkage for exess slak and adjust. Insure orret eletroni ontroller P/N has been installed. Replae the eletroni ontroller or instrument display. 4-7
4. Diagnosti Proedures Exessive Cruise Speed Loss on Hills <3 Step 1 Step 2 Step 3 Chek hoses for vauum leaks. Determine if hek valve is funtional. Chek vauum hose routing as shown on the under-hood deal, servie manual or appliable tehnial publiation. Corret as neessary. Slow Engage/Resume Response Step 1 Step 2 Step 3 Step 4 Chek for vauum hose restritions Chek for leaks in the vauum system. Perform vauum hose/devie repairs as neessary. Insure orret eletroni ontroller P/N has been installed. Custom Cruise III System Quik Cheker Three AC Custom Cruise III System Quik Cheker test units are available.. see figures 4-3, 4-4 and 4-5. 3 AVAILABILITY: Owatonna Tool Co. 144 Wimbleton Dr. Birmingham, Ml 48008 313-642-7766 AVAILABILITY: Kent-Moore Tool Co. 28635 Mound Rd. Warren, Ml 48092 313-539-5330 Figure 4-3, Quik Cheker Model No. ET-3475. Figure 4-4, Quik Cheker Model No. J-34185. 4-8
4. Diagnosti Proedures AVAILABILITY: SPECMO Enterprises 2344 N. Woodward Ave. Royal Oak, Ml 48073 313-399-5645 igure 4-5, Quik Cheker Model No. QC111 Quik Cheker Test Proedure Preparation... C 1. Remove kik pad to gain aess to module (ontroller) if appliable. 2. Depress harness onnetor loking tub and remove onnetor from module. 3. Connet tester to harness onnetor. Note: 12 terminal edgeboard onnetors mate to 1984 appliations, while 18 terminal onnetors mate to 1983 appliations. 4. Perform Steps 1-8, Table 4-4, Test Sequene. Pontia Fiero P Car Preparation C 1. Disonnet: edgeboard onnetor at instrument panel. 2. Observing key slots, onnet optional Pontia P Car adapter (figure 4-6) to Custom Cruise III Quik Cheker. 3. Observing the key slots in the male end of the optional adapter, fit male end to the female onnetor just removed from the instrument luster. 4. Perform tests as outlined for the Quik Cheker, exept for step 4. 5. To hek the PM generator and the wiring to the luster, proeed as follows: Roll drive wheels at an estimated 8 to 10 MPH. The LED molded into the lower end of the optional adapter should turn ON and OFF. ( r CAUTION If this test is being performed free running, support rear axle on jak stand. 4-9
4. Diagnosti Proedures QUICK CHECKER TEST SEQUENCE Step Test and Condition Corret Response Trouble Shooting for Inorret Response 1 System Not in Use Ign. ON, engine OFF mode ontrol swith OFF. No lights. Chek for shorted mode ontrol swith and/or related wiring. 2 Corret Power Soure Mode ontrol slider in ON position, ign. ON, engine OFF. ON/OFF and brake lights ON. (Note: vent, va SPS also light). Brake light OFF Chek luth and brake swithes and related wiring. ON/OFF OFF Chek for opens from fuse to Pin K of module. J 3 System Continuity Ign. ON, engine OFF and slider in ON position 4 Vehile Speed Sensor Performane Ign. ON, engine running slider in ON position, vehile moving at, or a simulated 5-10 MPH. All lights on exept R/A and S/C. VSS light should blink. Vent, Va, or SPS lights OFF Chek these solenoids or related wiring for ontinuity. Replae bad servo. Chek sender wiring VSS wiring and onnetions. Replae buffer amplifier or sender. J 5 Mode Control Swith Funtion Ing. ON, engine OFF and S/C depressed. S/C light lights, Va light goes out. Va short light does not light. Mode ontrol swith, servo, or related wiring bad. Immediately hek wiring between va terminal at ontroller and va terminal at servo for short to ground. J 6 Mode Control Swith Funtion Ign. ON, engine OFF and slider in R/A position. Table 4-4, Quik Cheker Test Sequene. R/A light lights, Vent light goes out. Vent short light does not light. Mode ontrol swith or related iruitry bad. Immediately hek wiring between vent terminal at ontroller and vent terminal at servo for short to ground. o 4-10
4. Diagnosti Proedures NOTE Do not depress S/C or R/A with engine running. If depressed, wide open throttle will our. rs QUICK CHECKER TEST SEQUENCE (ontinued) Step Test and Condition Corret Response Trouble Shooting for Inorret Response 7 Vauum System Chek Start and run engine for 1 minute to harge aumulator. Turn Engine OFF. Ign. ON. Depress S/C and R/A together. S/C and R/A lights, Vent and Va lights go out; Servo will full stroke and hold. Chek for restrited or leaking vauum soure. Then release S/C. Vauum should hold at full stroke servo position. Plug vauum release port (figure 2-11) and proeed to step 8. o 8 Vauum System Chek Start and run engine for 1 minute to harge aumulator. Turn Engine OFF. Ign. ON. Depress S/C and R/A together. Then release S/C. Vauum should hold at full stroke servo position. If it does, replae or servie vauum release valve, figure 2-6 (or figure 2-8 Pontia Fiero eletri vauum release valve) and/or related hoses. If it does not, replae servo. REFER TO QUICK CHECKER DEALER SERVICE MANUAL FOR ADDITIONAL INFORMATION 1
AC Spark Plug Division General Motors Corporation 1300 N. Dort Highway Flint, Mihigan 48556 U.S.A. Printed in U.S.A. SMCM-1A Litho in U.S.A. 8/83