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Signal Too Low






Signal too low

Checking the function of the oil temperature sensor




- Ignition on
- Read off the oil temperature.
Check that the temperature is within its permitted range.
Compare with the transmission temperature.

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





Was the transmission temperature within its permitted range?

Yes - Intermittent fault

No - Checking transmission fluid temperature sensor

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Checking transmission fluid temperature sensor








- Ignition off
- The transmission light gray 8-pin connector.
Check the temperature sensor by measuring the resistance between terminals #7 and #8 on the light gray 8-pin transmission connector.
The resistance must be 4.5-6 kohms at 20°C.





Was the resistance OK?

Yes - Checking the wiring and component

No - Checking the cable and component

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Checking the wiring and component
Check the cable between transmission control module (TCM) terminal #24 and terminal #7 on the light gray 8-pin transmission connector (control module side). Check for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Remedy as necessary.

Other information:
- To connect the breakout box, see Connecting the breakout box, AW55-50/51SN Connecting The Breakout Box
- To disconnect the transmission connectors, see Transmission connectors, AW55-50/51SN Transmission Connectors
- For information about signals, see Signal description. Transmission control module (TCM), AW55-50/51SN Signal Description.









Was a fault detected?

Yes - Verification

No - Checking the cable and component

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Checking the cable and component








- Ignition off
- Open the transmission control system.
Check the cable between terminal #7 on the light gray 8-pin transmission connector and temperature sensor terminal #1 and between transmission connector #8 and temperature sensor terminal #2. Check for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Also check the cables for a short-circuit to each other.

Hint: Check the temperature sensor. With the ignition off and the light gray 8-pin connector transmission disconnected, measure the resistance between connector terminals #7 and #8 (transmission side). The resistance must be 4.5-6 kohms at 20°C.

Remedy as necessary

Other information:
- To connect the breakout box, see Connecting the breakout box, AW55-50/51SN Connecting The Breakout Box
- To disconnect the transmission connectors, see Transmission connectors, AW55-50/51SN Transmission Connectors
- To open the transmission control system, see Replacing the cable harness for the control system, AW55-50/51SN Service and Repair
- To check and replace the temperature sensor, see Replacing the cable harness for the control system, AW55-50/51SN Service and Repair
- For information about signals, see Signal description. Transmission control module (TCM), AW55-50/51SN Signal Description.





Continue - Resetting the adaptation

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Resetting the adaptation





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

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DONE - Verification

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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.
Check that the transmission oil temperature is within its permitted range.
Compare with the transmission temperature.

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





Is the oil temperature within its permitted range?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFICATION FAILED - Fault-tracing information

VERIFIED - FAULT FOUND

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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 - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking the function of the oil temperature sensor

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Intermittent fault
Check the cable between transmission control module (TCM) terminal #24 and terminal #7 on the light gray 8-pin transmission connector (control module side). Check for a short-circuit to ground according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults. Also check the cables for a short-circuit to each other. For information about the cable routing, see the relevant Wiring Diagram.
Remedy as necessary.

Other information:
- To connect the breakout box, see Connecting the breakout box, AW55-50/51SN Connecting The Breakout Box
- To disconnect the transmission connectors, see Transmission connectors, AW55-50/51SN Transmission Connectors
- For information about signals, see Signal description. Transmission control module (TCM), AW55-50/51SN Signal Description.













Continue - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
It is possible to view the information again, or leave fault-tracing for this diagnostic trouble code (DTC).

Do you want to view the information again?

Yes - Attempt New Test

No - FAULT FOUND

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Attempt New Test - Checking the function of the oil temperature sensor

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