What does fault code TCM-05B1 mean?

Diagnostic fault code details for TCM-05B1 (Volvo C30 (2007–2013), Volvo C30 (2007–2013), Volvo C30 (2007–2013)). Repair service at OBD Tuning.

VOLVO

TCM-05B1 - Hydraulic pressure solenoid driver, even gears. Voltage too high

System

Transmission Control Module (TCM)

Volvo models this fault code applies to

Applies to the following models:

4 models

C30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)

Show models by year and engine (10)

What does this fault code mean?

The output stage for one of the solenoids in the transmission is shorted to supply voltage. The solenoids control the hydraulic pressure over the clutches, and this fault requires the mechatronic unit to be replaced. The cause may be a damaged solenoid, a damaged or dirty connector or circuit board, or a damaged transmission control module.

Possible causes

Damaged solenoid
Connector or circuit board damaged or dirty
Damaged transmission control module (TCM)

What you can do

1Read the fault codes, clear TCM-05B1 and drive the car to see whether it returns
2Have a workshop read the fault with diagnostic equipment. The fault requires the mechatronic unit to be replaced
3Have a workshop fit a new mechatronic unit and make sure the fault code does not come back

Symptoms you may notice3

Yellow warning symbol and text message in the display
Shifts hard or jerky
Shifts too early, too late or too often

General guidance for car owners. Diagnosis on the car can point to a different cause.