Diagnosis, Fault Memory (Page GR-D4) Anti-lock brake system (ABS) electrical testing self-diagnosis troubleshooting using electrical steps VAG 1551 Diagnostic Tester connecting erasing Fault memory reading Fault memory ABS troubleshooting
Anti-lock brake system (ABS), self-diagnosis (Page D4-10-1) Note Look under General for information about the test equipment, how to hook it up and how to use it. To use the information in this manual you need the right wiring diagram. See wiring diagrams. The ABS control unit (Part No. 357 907 379) has a permanent Fault memory. If problems occur at electrically monitored sensors or components they are stored in memory. Faults which occur occasionally are stored as sporadic faults. Faults are stored with varying priorities: solenoid faults have the highest priority and are displayed first. Sporadic faults have the lowest priority and are displayed last. If a fault is stored, the ABS indicator light (K 147) on the instrument panel will light up and, depending on the priority of the fault, ABS operation will be automatically switched off. The conventional braking system remains operational. A check sequence is performed by the ABS control unit (J 104) after the engine is started and the hydraulic pump builds up pressure in the accumulator. The ABS warning light will come on during this check but remains on only if a fault is present. The self-diagnosis must be initiated and the stored fault called up with the VAG 1551 tester. The VAG 1551 tester can access the ABS control unit memory via remote diagnostic terminals under the shift lever boot. Fault information must then be compared with the fault table/blink code in section D4-50 and the correct repair action taken.
VAG 1551 Diagnostic Tester, connecting (Page D4-20-1) CAUTION! Do not drive the vehicle with the VAG 1551 Diagnostic Tester connected. Requirements fuse, S16, S53, S54 OK - if not, check according to wiring diagram switch ignition OFF remove shift knob and shift lever boot connect the diagnostic cable, VAG 1551/1 for the tester VAG 1551: black plug (voltage supply) on black terminal A in vehicle white plug on gray terminal B in vehicle (if wire in terminal B is in position 2, reconnect it to position 1) blue plug not used VAG Self Diagnosis 1 - Rapid data transfer HELP VAG Self Diagnosis 2 - Blink code output HELP The displays will alternate as shown: Note For additional operating instructions push the HELP key. If no display appears, check the voltage supply to the tester. Pressing the key steps through the program.
Reading Fault memory, using VAG 1551 Diagnostic Tester (Page D4-30-1) VAG - self diagnosis 1 - Rapid data transfer HELP After connecting VAG 1551 diagnostic connector display will alternate and appear as shown: VAG - self diagnosis 2 - Blink code output HELP Note Press the PRINT button for a complete printout of fault functions. Blink code output is being initiated select operating mode 2, blink code output press button and hold, display will appear as shown Blink code output Permanent ground on exciter wire after approximately 2.5 seconds display will appear as shown: release button switch ON ignition ABS indicator (K 47) lights up Blink code XXXX operate button briefly, display shows: If a fault is stored it will appear via the indicator light (blinking) and in the tester display, e.g.: Blink code 1241 Speed sensor front right - G 45 operate button briefly to call up next blink code indicator light (K 47) blinks each fault in code, and display appears on screen as shown in example display Blink code 4444 No faults recognized! If display appears as shown: switch ignition OFF
self-diagnosis is complete Blink code output No blink code received! If display appears as shown check wire from terminals 26 and 27 of ABS control unit (J 104) to tester
Reading Fault memory, using VAG 1551 Diagnostic Tester (Page D4-30-2) Blink code 0000 End of output continue fault code call-up until display appears as shown: and then: Blink code output is completed! switch ignition OFF see fault table/blink code, section D4-50 and eliminate faults after repairs, switch ignition ON for approximately four seconds If indicator light (K 47) goes out, ABS is free of faults erase Fault memory (see section D4-40) If indicator light (K 47) does not go out read Fault memory again Note If more than one fault was displayed, faults which have been eliminated will also be shown again.
Erasing Fault memory using VAG 1551 (Page D4-40-1) Requirements Fault memory is recalled until blink code 0000 appears ignition is switched OFF and faults eliminated (see section D4-50) vehicle is test driven and a speed of at least 20 mph is attained CAUTION! The VAG 1551 Diagnostic Tester or any of its adaptor harnesses must not be connected during the test drive. read Fault memory, section D4-30 after blink code 0000 is displayed, Fault memory is erased repeat self-diagnosis after erasing Fault memory; diagnosis is complete only after fault code 4444 is displayed
ABS troubleshooting, using VAG 1551 (Page D4-50-1) 1 Refer to Electrical Testing/Troubleshooting charts provided.
ABS troubleshooting, using VAG 1551 (Page D4-50-2) 1 Refer to Electrical Testing/Troubleshooting charts provided.
ABS troubleshooting, using VAG 1551 (Page D4-50-3) 1 Refer to Electrical Testing/Troubleshooting charts provided.
ABS troubleshooting, using VAG 1551 (Page D4-50-4) 1 Refer to Electrical Testing/Troubleshooting charts provided.
ABS, electrical testing (Page D4-60-1) General notes When performing electrical troubleshooting, refer to the wiring diagrams, and the test steps which follow. These steps apply to: 1 - vehicles without the self-diagnosis feature (up to VIN JE 048 300) 2 - vehicles for which the self-diagnosis feature does not determine the problem source Note In both cases: perform Test steps 1-37, in sequence perform only those procedures marked by " ". Those marked with " " have already been performed 3 - vehicles with the self-diagnosis feature: perform only those test steps recommended in the Blink Code Troubleshooting charts perform all procedures marked with either " " or " " Testing equipment VAG 1598, Test box VAG 1598/3, adaptor VAG 1594, connector test kit US 1119, multi-meter (or equivalent) Note Hoist equipment for raising/supporting vehicle is also needed (Test steps 5-8, 35-37). Preliminary checks verify that fuses, S16, S53, and S54 are OK verify that ground wire near control unit is OK be sure ignition remains OFF during all test steps
ABS, electrical testing (Page D4-60-2) Testing equipment, connecting connect ABS control unit's multi-pin terminal to VAG 1598, using adaptor VAG 1598/3. the control unit is not connected A = control unit specified test values are verified for US 1119 only, and are not necessarily applicable to other testing equipment
ABS troubleshooting, using electrical test steps (Page D4-70-1)
ABS troubleshooting, using electrical test steps (Page D4-70-2)
ABS troubleshooting, using electrical test steps (Page D4-70-3)
ABS troubleshooting, using electrical test steps (Page D4-70-4)
ABS troubleshooting, using electrical test steps (Page D4-70-5)
ABS troubleshooting, using electrical test steps (Page D4-70-6)
ABS troubleshooting, using electrical test steps (Page D4-70-7)
ABS troubleshooting, using electrical test steps (Page D4-70-8)
ABS troubleshooting, using electrical test steps (Page D4-70-9)
ABS troubleshooting, using electrical test steps (Page D4-70-10)