VOLVO
TCM-0403 - Shift fork 1. Faulty signal
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 position sensor signal for shift fork 1 changes too quickly, which the transmission control module (TCM) reacts to. The fault is linked to that sensor, but whether the cause is in the sensor or in the transmission only becomes clear after the other fault codes have been read out.
Possible causes
- Damaged position sensor
- Incorrect voltage supply to the sensor
- Damaged transmission control module (TCM)
What you can do
- 1Read out the fault codes from the transmission control module again to find out whether the fault is in the transmission or in the mechatronic unit
- 2If you have diagnostic equipment, look at the position value for shift fork 1 in live data and see whether it changes quickly or unevenly when the gears are engaged
- 3If fault code TCM-0428 is set, the cause lies outside the mechatronic unit, mechanical or hydraulic, and a workshop should replace the transmission
- 4If any of the sensor fault codes TCM-0400, TCM-0401 or TCM-0405 is set but not TCM-0428, this points to a sensor fault and a workshop should replace the mechatronic unit
- 5If none of the codes above is set, a workshop should compare the counter values for the fault code to decide whether it is a sensor or a mechanical fault
Symptoms you may notice5
- Check engine light comes on or behaves abnormally
- Yellow warning symbol and message in the display
- Gear changes take too long to complete, sometimes or all the time
- Gears shift hard or jerky, sometimes or all the time
- Gears shift too early, too late or too often, sometimes or all the time
General guidance for car owners. Diagnosis on the car can point to a different cause.