VOLVO
ECM-B12A64B - Auxiliary Heater Water Pump. System Internal Failures. Over temperature
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 (11)
- 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–)2011–2012Engine D4162T only
- Volvo V60 (2011–)2013–2014Engine D4162T, D82PHEV only
- Volvo V60 (2011–)2015Engine D4162T, D82PHEV, D87PHEV only
- Volvo V70 (2008–)2012–2015Engine D4162T only
What does this fault code mean?
The code points to a probable overload in the coolant pump relay. The engine control module sets it when it judges that this is the case, and the coolant pump is then switched off. Causes can include loose or shorted connections, or a damaged pump or damaged wiring to the pump.
Possible causes
- Loose connection or oxidation in the connector
- Short circuit on the connections
- Damaged coolant pump relay
- Damaged pump
- Short circuit or open circuit in the wiring to the pump
What you can do
- 1Check that the relevant fuses are intact and that the connectors at the coolant pump relay are fully seated
- 2With a multimeter, check that there is no short circuit in the connections to the relay and to the pump
- 3If the connectors and wiring are sound, the pump or relay may be damaged; have a workshop check and replace the faulty part
Symptoms you may notice4
- Uneven temperature in the cabin
- HYBRID drive mode is used all the time or too often, with the combustion engine running
- The parking heater does not work
- Text window with a warning symbol and text message
What the fault can affect1
- The coolant pump is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.