VOLVO
ECM-P029984 - Turbocharger/Supercharger A Underboost Condition. Bus Signal / Message Failures. Signal below allowable range
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
9 modelsC30 (2007–2013), S40 (2004–2013), S60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V50 (2004–2013), V60 (2011–), V70 (2008–)
Show models by year and engine (9)
- Volvo C30 (2007–2013)2011–2013Engine D4162T only
- Volvo S40 (2004–2013)2011–2012Engine D4162T only
- Volvo S60 (2011–)2011–2015Engine D4162T only
- Volvo S80 (2007–)2012–2015Engine D4162T only
- Volvo V40 (2013–)2013–2015Engine D4162T only
- Volvo V40 Cross Country (2013–)2013–2015Engine D4162T only
- Volvo V50 (2004–2013)2011–2012Engine D4162T only
- Volvo V60 (2011–)2011–2015Engine D4162T only
- Volvo V70 (2008–)2012–2015Engine D4162T only
What does this fault code mean?
The code concerns the control signal from the engine control module (ECM) to the turbo control valve, which falls outside its permitted limit. The turbo control valve sets the intake manifold pressure by acting on the pressure capsule that controls the turbine position. The code is stored when the control signal falls outside its limits, and it is general.
Possible causes
- Air leak in the intake system between the turbo and the boost pressure sensor
- Clogged hoses to the turbo unit or the turbo control valve
- Damaged turbo control valve
What you can do
- 1Read and note the fault code, clear it and test drive to see whether it returns
- 2Check the intake system between the turbo and the boost pressure sensor for leaks
- 3Check the hoses to the turbo unit and the turbo control valve for blockage
- 4Have a workshop with diagnostic equipment check the turbo control valve
Symptoms you may notice1
- The Check engine light comes on or behaves abnormally
What the fault can affect1
- Exhaust gas recirculation (EGR) control stops
General guidance for car owners. Diagnosis on the car can point to a different cause.