ECM-P029900 - Turbocharger/Supercharger A Underboost Condition. General Failure Information. No sub type information
System
Engine Control Module (ECM)
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:
12 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), S60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V50 (2004–2013), V60 (2011–), V70 (2008–), XC60 (2009–), XC70 (2008–)
Show models by year and engine (41)
- Volvo C30 (2007–2013)2011–2013Engine D4162T, D5204T, D5204T5 only
- Volvo C70 (2006–2013)2011Engine D5204T, D5204T5 only
- Volvo C70 (2006–2013)2012–2013All engines except: B5254T7
- Volvo S40 (2004–2013)2011–2012Engine D4162T, D5204T, D5204T5 only
- Volvo S60 (2011–)2011Engine D4162T, D5204T2, D5244T10 only
- Volvo S60 (2011–)2012Engine D4162T, D5204T3, D5244T11, D5244T15 only
- Volvo S60 (2011–)2013–2014Engine D4162T, D5204T3, D5204T7, D5244T11, D5244T15 only
- Volvo S60 (2011–)2015Engine D4162T, D5204T3, D5204T7, D5244T11, D5244T15, D5244T23 only
- Volvo S80 (2007–)2009Engine D5244T10 only
- Volvo S80 (2007–)2010Engine D5244T10, D5244T14, D5244T19 only
- Volvo S80 (2007–)2011Engine D5204T2, D5244T10 only
- Volvo S80 (2007–)2012Engine D4162T, D5204T3, D5244T11, D5244T15 only
- Volvo S80 (2007–)2013–2014Engine D4162T, D5204T3, D5204T7, D5244T11, D5244T15 only
- Volvo S80 (2007–)2015Engine D4162T, D5204T3, D5244T15 only
- Volvo V40 (2013–)2013–2014Engine D4162T, D5204T4, D5204T6 only
- Volvo V40 (2013–)2015Engine D4162T, D5204T6 only
- Volvo V40 Cross Country (2013–)2013–2014Engine D4162T, D5204T4, D5204T6 only
- Volvo V40 Cross Country (2013–)2015Engine D4162T, D5204T6 only
- Volvo V50 (2004–2013)2011–2012Engine D4162T, D5204T, D5204T5 only
- Volvo V60 (2011–)2011Engine D4162T, D5204T2, D5244T10 only
- Volvo V60 (2011–)2012Engine D4162T, D5204T3, D5244T11, D5244T15 only
- Volvo V60 (2011–)2013Engine D4162T, D5204T3, D5204T7, D5244T11, D5244T15, D5244T17, D82PHEV only
- Volvo V60 (2011–)2014Engine D4162T, D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17, D82PHEV only
- Volvo V60 (2011–)2015Engine D4162T, D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17, D5244T23, D82PHEV, D87PHEV only
- Volvo V70 (2008–)2009Engine D5244T10 only
- Volvo V70 (2008–)2010Engine D5244T10, D5244T14, D5244T19 only
- Volvo V70 (2008–)2011Engine D5204T2, D5244T10 only
- Volvo V70 (2008–)2012Engine D4162T, D5204T3, D5244T11, D5244T15 only
- Volvo V70 (2008–)2013Engine D4162T, D5204T3, D5204T7, D5244T11, D5244T15, D5244T17 only
- Volvo V70 (2008–)2014Engine D4162T, D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17 only
- Volvo V70 (2008–)2015All engines except: B4164T, B4164T2, B4204T11, B5204T9, B6304T4, D4204T5
- Volvo XC60 (2009–)2010Engine D5244T10, D5244T14, D5244T16 only
- Volvo XC60 (2009–)2011Engine D5204T2, D5244T10, D5244T16 only
- Volvo XC60 (2009–)2012Engine D5204T3, D5244T11, D5244T15, D5244T17 only
- Volvo XC60 (2009–)2013All engines except: B4204T7, B6304T4, B6324S4, B6324S5
- Volvo XC60 (2009–)2014Engine D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17 only
- Volvo XC60 (2009–)2015Engine D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17, D5244T23 only
- Volvo XC70 (2008–)2010Engine D5244T10, D5244T14, D5244T16 only
- Volvo XC70 (2008–)2011Engine D5204T2, D5244T10, D5244T16 only
- Volvo XC70 (2008–)2012–2013All engines except: B6304T4, B6324S4, B6324S5
- Volvo XC70 (2008–)2014–2015Engine D5204T3, D5244T11, D5244T12, D5244T15, D5244T17 only
What does this fault code mean?
The engine control module (ECM) keeps watch on the turbo system and its parts. The code is stored when the boost pressure falls below the permitted limit. The turbo pressure is controlled by a turbo control valve that affects the position of the turbine, and a fault may come from leaks, sticking or damage in the system. The code is general and does not say what type of fault it is.
Possible causes
- Air leak in the intake system
- Sticking guide vanes, a damaged turbo control motor or a damaged turbo unit
- Damaged turbo control valve, or damaged or clogged vacuum hoses
- Damaged pressure actuator for the turbo control valve (VNT regulator)
- The EGR valve has stuck open, or the passive EGR bypass valve is damaged
- Damaged turbo control valve A (wastegate) or B (bypass), or a clogged exhaust system
What you can do
- 1Read and note the fault codes; if ECM-P003A85 is stored, deal with that code first, since it points to an adaptation fault in the turbo
- 2Check that the intake system is airtight, with no leaks or cracks in the hoses and clamps
- 3Check that the turbo control motor and the turbo control valve are not sticking and that the vacuum hoses are intact, clean and correctly fitted
- 4Check the EGR valve and the passive bypass valve for damage and that they have not stuck open
- 5If you have a diagnostic tool: read the intake air temperature sensor value and check that it is reasonable when the engine is warm
- 6Have a workshop with diagnostic equipment check the turbo unit and its valves
Symptoms you may notice3
- The car lacks power
- A message in the display together with a warning symbol
- The Check engine light comes on or behaves abnormally
What the fault can affect2
- Engine output is limited
- Exhaust gas recirculation (EGR) control stops
General guidance for car owners. Diagnosis on the car can point to a different cause.