What does fault code TCM-P073179 mean?

Diagnostic fault code details for TCM-P073179 (Volvo S60 (2011–), Volvo S80 (2007–), Volvo V40 (2013–)). Repair service at OBD Tuning.

VOLVO

TCM-P073179 - Gear 1 Incorrect Ratio. Mechanical Failures. Mechanical linkage failure

System

Transmission Control Module (TCM)

Volvo models this fault code applies to

Applies to the following models:

9 models

S60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)

Show models by year and engine (9)

What does this fault code mean?

The transmission control module (TCM) has selected a gear whose ratio is close to that of another gear. The fault is described as a mechanical linkage failure in the transmission, where clutch C2 or brake B1 may be engaged unintentionally. The fault concerns 1st gear.

Possible causes

Contact resistance or poor contact in the connectors to the linear pressure solenoids
One or more of the linear pressure solenoids has stuck or is damaged
A fault inside the TCM or its control system
Mechanical faults in the transmission

What you can do

1First check whether the transmission has more fault codes; they may be the root fault and should be dealt with first
2Clear the code and road test the car in first gear with engine braking to see whether it returns
3Have a workshop check the connectors and wiring to the affected solenoids
4If the solenoids are sound, have a workshop look for any mechanical damage inside the transmission

Symptoms you may notice5

Yellow warning symbol and text message in the display
The car may feel underpowered
No automatic gear change
No forward or reverse movement in gear
Gear changes happen too early, too late or too often

What the fault can affect1

Adaptation function is blocked

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