INTERACTIVE DISTANCE LEARNING ANTI-LOCK BRAKE SPECIALIST: KELSEY HAYES FOUR WHEEL ANTI-LOCK BRAKING SYSTEMS 4WAL LEARNING GUIDE

Transcription

1 INTERACTIVE DISTANCE LEARNING ANTI-LOCK BRAKE SPECIALIST: KELSEY HAYES FOUR WHEEL ANTI-LOCK BRAKING SYSTEMS 4WAL LEARNING GUIDE CARS KNOWLEDGE NETWORK Leslie Street Richmond Hill, ON L4B 3J9 Phone: Fax: askus@cars-council.ca

2 KELSEY- HAYES 4WAL Learning Outcome Upon successful completion of this segment the participants will be able to identify and test system and individual 4WAL components. Additionally the participant will be able to utilize manuals and test equipment to diagnose component and system failures. Objectives Upon successful completion, the participants will be able to perform the following: 1. Describe normal and ABS functions and state vehicle applications 2. Locate and identify 4WAL electrical and hydraulic components and describe their functions. 3. Identify 4WAL inputs and outputs and describe their functions 4. Identify 4WAL hydraulic system components and their functions 5. Illustrate different modes of 4WAL braking 6. Identify system and component failures by utilizing manuals and test equipment 2

3 KELSEY-HAYES 4WAL Kelsey Hayes four-wheel antilock (4WAL) is used on General Motor light duty trucks. List below some of the applications: Kelsey Hayes four-wheel antilock (4WAL) is classified as a: The 4WAL system uses 3 separate channels and they are: The term " Select Low" is used by the EBCM and it is defined as: List below some of the base brake components that are used: 3

4 List the components that have been added to the base brake components: Typical 4 WAL ECHU Assembly The EBCM has 3 different connectors and they are: 1. - wheel speed sensors 2. - inputs and outputs 3. - pump and solenoids 4

5 Electronic Brake Control Module (EBCM) The purpose of the EBCM is to: WAL EBCM The EBCM is located: Brake Pedal and Brake Switch Assembly 5

6 The purpose of the brake switch is to: The brake switch will input a volt input to the EBCM when the pedal is depressed. Pump Motor The purpose of the pump motor is to: Pump Motor The Pump Motor is located:. Pump Motor Relay The purpose of the Pump Motor relay is: 6

7 Pump Motor Relay The Pump Motor Relay is located: High Pressure Accumulator The purpose of a high-pressure accumulator is: EHCU-bottom view 7

8 Hydraulic Control Unit The purpose of the hydraulic unit or valve body is: Pulse Width Modulation Solenoids Wheel Speed Sensors (WSS) The purpose of the WSS is to: WSS- FRONT HUB ASSEMBLY WSS- REAR SENSOR 8

9 The WSS depending on whether it is a 3 or 4 sensor system can be located: List below some of the other components that are used and their purpose: NOTES 9

10 Modes of Operation 4WAL IN NON-ANTILOCK MODE Colour in the flow of brake fluid NOTES 10

11 4WAL DURING PRESSURE HOLD MODE Colour in the flow of brake fluid NOTES 11

12 4WAL IN PRESSURE DECREASE MODE Colour in the flow of brake fluid NOTES 12

13 4WAL IN PRESSURE INCREASE MODE Colour in the flow of brake fluid NOTES 13

14 System Diagnostics Customer Information List some of the comments or concerns that your customers may have regarding their ABS: Road Testing and Visual Inspection List some of the things that may be determined through both of these actions: Amber ABS Warning Light The purpose of the Amber ABS light is to: The Amber ABS light will remain illuminated for approximately seconds if there are no problems. 14

15 Red Brake Warning Lamp (RBWL) The purpose of the Red Brake light is to: Powers and Grounds Supplied to the EBCM are 2 power inputs: Fusible link - Fused B+ - There are 3 ground circuits to be checked and they should have no more than volts on them. Diagnostic Trouble Codes ( DTC's ) The EBCM will generate a DTC when: 15

16 DTC 's can be extracted through the utilization of a Scan tool or through a manual retrieval method that is performed by: List below the procedure to extract DTC 's throough the utilization of blinking the Amber ABS warning lamp: There are 2 basic code distinctions and they are:

17 There are different methods of clearing DTC's and they are : Some of the scantool tests that can be performed are: Bleeding the 4WAL system may be necessary if: NOTE: Consult Service Literature for the proper sequence and safety precauions to be followed. NOTES 17