Chassis Number 26212 and Prior

Faulty signal. Permanent fault

Checking the vehicle speed sensor (VSS) signal








- Ignition off.
- Check the control module and vehicle speed sensor (VSS) connectors for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
- Reinstall the components, reconnect the connectors etc.
- Raise the car so that the drive wheels can rotate freely.
- Engine idling.
- Gear selector in position D.
- Read off the transmission speed signal.
Check that the speed increases with engine speed (RPM). If the speed is updated, the cause of the fault was loose connections in the control module or vehicle speed sensor (VSS) connectors.

Note! A diagnostic trouble code (DTC) may be stored in the ABS system when the rear wheels are stationary and the front wheels rotate. Erase any diagnostic trouble codes (DTCs) in the ABS system after completing fault-tracing.

Other information:
- To disconnect the transmission control module (TCM), see Transmission control module (TCM), replacing, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Service and Repair.
- To disconnect the transmission connector, see the relevant service procedure.
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).





Does the speed increase with engine speed (RPM)?

Yes - Fault Found

No - Checking wiring and sensors

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Checking wiring and sensors




- Ignition off.
- Connect the breakout box.
Check the power supply cable between vehicle speed sensor (VSS) connector terminal #1 (control module side) and control module terminal #57 (#A57). Check for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check the signal cable between vehicle speed sensor (VSS) connector terminal #2 (control module side) and control module terminal #39 (#A39). Check for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Hint: With the control module connected, the vehicle speed sensor (VSS) disconnected and the ignition on, the voltage between vehicle speed sensor (VSS) connector terminals #1 and #2 should be approximately 1-3 V below Ubat.

Remedy as necessary.

Other information:
- To connect the breakout box, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box.
- To disconnect the transmission connector, see the relevant service procedure.
- To check or replace the vehicle speed sensor (VSS), see Transmission output speed sensor, replacing Transmission Output Speed Sensor, Replacing.
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).









Was a fault detected?

Yes - Verification

No - No Fault Found

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Verification




Verification

Hint: After carrying out the repair, check that the fault has been remedied.








- Ignition off.
- Reinstall connectors, components etc.
- Raise car so that drive wheels are unimpeded.
- Start the engine and let it idle.
- Shift gear selector to position D so that the drive wheels begin to rotate.
- Read off the transmission speed.
Check that speed is updated

Note! When the rear wheels are stationary and the front wheels rotate, diagnostic trouble codes (DTCs) can be stored in the ABS system. Erase any diagnostic trouble codes (DTCs) stored in the ABS system after fault-tracing.

Note! Ensure that the wheels are not rotating when the gear selector is moved.





Was speed updated?

Yes - VERIFIED

No - VERIFICATION FAILEDPAPER

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VERIFIED - Fault Found

VERIFICATION FAILED - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.

Do you want to exit fault-tracing?

Yes - FAULT-TRACING FAILED

No - Attempt New Test

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FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Checking the vehicle speed sensor (VSS) signal

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