VOLVO
TCM-019B - Gear selector module (GSM). Signal too low
System
Transmission Control Module (TCM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (6)
- Volvo C30 (2007–2013)2007–2013Transmission AW55-50/51SN only
- Volvo C70 (2006–2013)2006–2013Transmission AW55-50/51SN only
- Volvo S40 (2004–2013)2004, 2011–2012Transmission AW55-50/51SN only
- Volvo S40 (2004–2013)2005–2010Transmission AW50/51 AWD, AW55-50/51SN only
- Volvo V50 (2004–2013)2004, 2011–2012Transmission AW55-50/51SN only
- Volvo V50 (2004–2013)2005–2010Transmission AW50/51 AWD, AW55-50/51SN only
What does this fault code mean?
Although the fault code is named too low signal, the gear selector module (GSM) has no power supply. Manual gear changes are then not possible, and the indication of the selected gear on the top of the selector does not work.
Possible causes
- Contact resistance in the connector
- Power supply wire short-circuited to ground
- Open circuit in the power supply wire
What you can do
- 1Check the fuse for the gear selector and the battery voltage
- 2Depress the brake, move the selector to manual mode and towards + and -, and check that the selected gear updates in the display
- 3Use a multimeter to check that power reaches the gear selector and that the wire is not short-circuited to ground
- 4Have a workshop check the gear selector connector for contact resistance
- 5If no wiring fault is found, have a workshop replace the gear selector module
Symptoms you may notice3
- The general warning lamp is lit
- No manual gear shift
- The gear selector indication does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.