VOLVO
TCM-0491 - Temperature sensor control module. Signal outside its permitted range
System
Transmission Control Module (TCM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (10)
- Volvo C30 (2007–2013)2008Engine D4204T only · Transmission MPS6 only
- Volvo C30 (2007–2013)2009–2010Engine B4204S3, D4204T only · Transmission MPS6 only
- Volvo C30 (2007–2013)2011–2013Engine B4204S3 only · Transmission MPS6 only
- Volvo C70 (2006–2013)2009–2010Engine D4204T only · Transmission MPS6 only
- Volvo S40 (2004–2013)2008Engine D4204T only · Transmission MPS6 only
- Volvo S40 (2004–2013)2009–2010Engine B4204S3, D4204T only · Transmission MPS6 only
- Volvo S40 (2004–2013)2011–2012Engine B4204S3 only · Transmission MPS6 only
- Volvo V50 (2004–2013)2008Engine D4204T only · Transmission MPS6 only
- Volvo V50 (2004–2013)2009–2010Engine B4204S3, D4204T only · Transmission MPS6 only
- Volvo V50 (2004–2013)2011–2012Engine B4204S3 only · Transmission MPS6 only
What does this fault code mean?
The temperature sensor in the transmission control module (TCM) gives a signal outside its normal range. The sensor is built into the processor and reads its internal temperature, so the control module receives wrong information about that temperature.
Possible causes
- The sensor is damaged
What you can do
- 1Read out the fault codes from the transmission control module and deal first with any codes that may share the same cause
- 2With diagnostic equipment, read the oil temperature from both sensors in live data with the transmission at room temperature
- 3After a short road test with some gear changes, read the oil temperature again; both sensors should have risen by about the same amount
- 4If the readings are not reasonable, the fault is permanent. If they are reasonable and agree, it was probably present earlier but is not active now
- 5If the fault is inside the control module or its components, the mechatronic unit must be replaced, which a workshop should do
Symptoms you may notice1
- No noticeable symptoms for the driver
General guidance for car owners. Diagnosis on the car can point to a different cause.