VOLVO
TCM-0120 - Control unit. Internal fault
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:
7 modelsS40 (1996–2004), S60 (2001–2009), S80 (1999–2006), V40 (1996–2004), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (17)
- Volvo S40 (1996–2004)2001–2004
- Volvo S60 (2001–2009)2001–2002
- Volvo S60 (2001–2009)2003All transmissions except: M58
- Volvo S60 (2001–2009)2004–2009Transmission AW50/51 AWD, AW55-50/51SN only
- Volvo S80 (1999–2006)1999–2000Transmission AW55-50/51SN only
- Volvo S80 (1999–2006)2001–2006Transmission AW50/51 AWD, AW55-50/51SN only
- Volvo V40 (1996–2004)2001–2004
- Volvo V70 (2000–2008)2000–2002
- Volvo V70 (2000–2008)2003All transmissions except: M58
- Volvo V70 (2000–2008)2004–2007Transmission AW50/51 AWD, AW55-50/51SN only
- Volvo V70 (2000–2008)2008Transmission AW55-50/51SN only
- Volvo V70 XC / XC70 (2001–2007)2001–2002
- Volvo V70 XC / XC70 (2001–2007)2003–2007Transmission AW50/51 AWD only
- Volvo XC90 (2003–)2003All transmissions except: 4T65 AWD
- Volvo XC90 (2003–)2004–2007Transmission AW50/51 AWD, AW55-50/51SN only
- Volvo XC90 (2003–)2008–2014Transmission AW50/51 AWD only
- Volvo XC90 (2003–)2015
What does this fault code mean?
The control module has detected an internal fault in the output driver circuit that controls one of the solenoids in the gearbox. The fault lies in the control module, which can then cancel activation of the solenoids.
Possible causes
- Internal fault inside the TCM
What you can do
- 1Clear the fault code and road test to see whether it comes back
- 2If you have a diagnostic tool: activate solenoid S3 and check that its status changes between off and on
- 3Have a workshop check the control module and, if needed, replace and program it, since a new control module must be programmed
- 4Do not replace other parts before a workshop has checked the control module
Symptoms you may notice5
- The orange general warning lamp is lit
- The lock-up function does not work
- Harsh gear changes
- Gear changes do not occur
- The automatic transmission warning lamp flashes
What the fault can affect2
- The transmission limp-home program Limp-home is activated
- System pressure is not reduced during gear changes and no torque limiting is requested from the engine control module
General guidance for car owners. Diagnosis on the car can point to a different cause.