Faulty Signal

Faulty signal

Checking transmission fluid temperature sensor

Note! During this fault-tracing, the transmission and the oil should be at normal room temperature from the start in order to check the sensor function.




- Ignition on
- Read off the oil temperature
- Start the engine. Allow the engine to idle. Apply the parking brake and brake with the foot brake. Then engage gear D. Keep the brakes applied.
Allow the transmission to warm up. Check that the oil temperature increases and appears to be within the permitted range. Compare with the transmission temperature.

Note! The transmission temperature sensor is located inside the control system and may be affected by the heat given off by the solenoids.

The fault is permanent if the temperature is outside the permitted range.
If the temperature is within the permitted range, this is an indication that the fault was present previously but that it is not active at the moment, i.e. the fault is intermittent.

Oil Temperature Sensor:

Continue - Checking cable and component

-------------------------------------------------

Checking cable and component








- Ignition off
- Expose the transmission control system.
Check connector C (22-pin) for the transmission control module (TCM). Check for contact resistance. Check for oxidation.
Try a new oil temperature sensor if no fault is found in the connector.
Remedy as necessary.

Other information
- Transmission control module (TCM) Service and Repair
- Cover, control system, B5254T7, AW55-50/51SN Cover, Control System
- Signal specification, AW55-50/51SN Signal Specification, Transmission Control Module (TCM)
- Component resistance values, AW55-50/51SN [1][2]Specifications
- Checking wiring and terminals Checking Wiring and Terminals

Oil Temperature Sensor:

Continue - Resetting adaptation and oil quality counter

-------------------------------------------------

Resetting adaptation and oil quality counter





Resetting the Transmission fluid change counter

Resetting the Transmission fluid change counter

Hint: The transmission control module (TCM) has a counter for the oil quality. The counter counts up if the transmission is exposed to too high a load or an ambient temperature that is too high. If the counter is not reset when the oil is drained or changed, there is a risk that a diagnostic trouble code (DTC) will be stored incorrectly. Therefore it is important that the "Transmission oil change" counter is reset.

Note! This only applies when the transmission fluid is changed and when the fluid is changed during repairs to the transmission temperature sensor.




- Ignition on.
Click on the VCT2000 symbol to reset the counter.





Continue - DONE

------------------------

DONE - Verification

-------------------------------------------------

Verification




Verification

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








- Ignition off
- Reinstall the connectors, components etc.
- Ignition on
- Read off the oil temperature for the transmission control module (TCM).
Check that the oil temperature is within its permitted range. Compare it to the automatic transmission temperature.

Note! The transmission temperature sensor is located inside the control system and may be affected by the heat given off by the solenoids.









Is the temperature OK?

Yes - VERIFIED

No - VERIFICATION FAILED

------------------------

VERIFICATION FAILED - Fault-tracing information

VERIFIED - FAULT FOUND

-------------------------------------------------

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 - Exit fault-tracing

No - Attempt New Test

------------------------

Attempt New Test - Checking transmission fluid temperature sensor

-------------------------------------------------