Motor Vehicle Level 3

1. Motor Vehicle Level 3 Resource 6 Anti-Lock Braking System Diagnostics

2. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Aims Recognise the diagnostics procedures within ABS systems

3. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Objectivies By the end of the session you will be able to: 1) Recognise the tools used to diagnose faults within ABS systems 2) List a diagnostic procedure for diagnosing a fault within ABS systems 3) Recognise different types of diagnostic systems.

4. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics On board and Off board diagnostic • ON board diagnostic refers to a self diagnostic procedure that the vehicle performs during start up • OFF board diagnostic refers to diagnostic done by a technician via a scan tool.

5. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Diagnostic tools. Diagnostic tools could include the following:- • Multi meter • Hand scan tool • Sun diagnostic Machine/computer • based diagnostic system

6. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Diagnostic tools Multi-meter • A multi meter is used to read voltages (AC and DC), current and resistance through a circuit. • It can also be used to measure continuity throughout a circuit. • The scale can be altered to suit the amount of voltage etc that you are measuring.

7. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Diagnostic Tools Hand Scan tools • Is plugged into the vehicle via the OBDII port. • Shows trouble codes in order to aid diagnostic of a system fault. • This is the most common method

8. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Diagnostic Tools Sun diagnostic machine/computer based diagnostic software • Similar to a scan tool is used to show diagnostic codes, however waveform patters can also be shown. • Software can be uploaded to the technicians laptop

9. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Diagnostic Function • When a fault occurs within a vehicle’s system a MIL (Malfunction Indicator Light) lights up to display to the driver that there is a fault.

10. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Diagnostic Function • The vehicle will then store a code within the vehicles ECU so that a technician can access it via a scan tool (hand scanner or Sun diagnostic machine) • The technician can now begin to solve the problem(s) within that system

11. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics How to access the trouble codes There are various methods that the technician can use to access the code. This could include • OBD II port • Blink Codes

12. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics How to access the trouble codes Blink Codes • Sometimes known as flash codes • Once the scan tool has been connected a LED will light for a considerable while. • After which the LED will begin to flash a code (similar to Morse code) which the technician records. • The technician can then detect where the problem on the system by looking up the code within the specification documentation. • The LED will illuminate for a long time to show that the code has finished being transmitted.

13. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics How to access the trouble codes OBD port • The most common way of accessing the fault code is via the diagnostic port. • This is normally located within the passenger foot well • This is the location within vehicles after 2000 (EOBD), • For vehicles before this year-see manufacture spec.

14. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics How to access the trouble codes • Once the scan tool has been connected to the vehicle, the technician can scan the ECU for a trouble code. • This is shown on the tool itself • The technician can now refer to the specification documentation in order to resolve the systems fault. • Some EOBD scan tools can also show live data and waveforms

15. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics How to access the trouble codes • Scan tools come with a set of cartridges. • Each cartridge has diagnostic information regarding each manufacture. • These are updated as vehicles change or new models are released

16. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Trouble codes • OBD (before 2000) has three to five digit codes • EOBD (after 2000) have a standardised code. • After the fault has been repaired it is important that the code is then cleared via the scan tool.

17. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics How to access the trouble codes Activity • In groups of three discuss the advantages and disadvantages of each system.

18. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Typical diagnostic procedure A customer has come to your workshop stating that the ABS light is on. • Individually write a diagnostic procedure for the sequence you would conduct in order to solve the problem.

19. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Typical diagnostic procedure • Confirm with the customer (customer service) what the fault is and symptoms. (if possible road test with the customer) • Ensure the correct cartridge/key is in the scan tool • Connect to the OBD port • Switch on Ignition

20. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Typical diagnostic procedure • Enter the vehicles details (VIN number) • Retrieve code from ECU (refer to tool manual) • Refer to manual with regards to the vehicle code • Repair the fault. • Ensure all codes are cleared from ECU • Remove scan tool

21. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Typical diagnostic procedure • Road test the vehicle to ensure that the fault has cleared

22. Motor Vehicle Level 3Resource 6 Anti-Lock Braking System Diagnostics Summary Have we:- • 1) Recognised the tools used to diagnose faults within ABS systems • 2) Listed the steps within a diagnostic procedure for diagnosing a fault within ABS systems • 3) Recognised different types of diagnostic systems.