VOLVO
ECM-P064100 - Sensor Reference Voltage A Circuit/Open. General Failure Information. No sub type information
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsS60 (2011–), S80 (2007–), V70 (2008–), XC90 (2003–)
Show models by year and engine (10)
- Volvo S60 (2011–)2011–2012Engine B5254T5 only
- Volvo S80 (2007–)2007–2008Engine B5254T6 only
- Volvo S80 (2007–)2009Engine B5254T6, B5254T8 only
- Volvo S80 (2007–)2010–2011Engine B5254T10, B5254T11, B5254T8 only
- Volvo S80 (2007–)2012Engine B5254T10 only
- Volvo V70 (2008–)2008Engine B5254T6 only
- Volvo V70 (2008–)2009Engine B5254T6, B5254T8 only
- Volvo V70 (2008–)2010–2011Engine B5254T10, B5254T11 only
- Volvo V70 (2008–)2012Engine B5254T10 only
- Volvo XC90 (2003–)2005–2011Engine B8444S only
What does this fault code mean?
The engine control module (ECM) monitors reference voltage A to the sensors. The code is set when the module finds a voltage problem in any internal supply circuit to a component: too high, too low, or no voltage at all. The cause may be in the wiring or a sensor, but it can also be the engine control module itself.
Possible causes
- Signal cable for the connected component short-circuited to supply voltage
- Open circuit in the signal cable for the connected component
- Signal cable for the connected component short-circuited to ground
- Supply cable to the sensor short-circuited to ground or supply voltage
- Damaged sensor
- Damaged engine control module (ECM)
What you can do
- 1Read the fault codes and first trace any stored codes for sensors supplied from the engine control module
- 2Check that the relevant fuses are intact and that the connectors to the engine control module and the sensors are secure, with no play or oxidation
- 3Use a multimeter to check that the wires from the engine control module to the sensors have no open circuit and are not shorted to ground or supply voltage
- 4If the wiring is intact and the fault remains, have a workshop determine whether a sensor or the engine control module is damaged
Symptoms you may notice5
- Uneven idle and increased emissions
- Poor performance
- The engine stops while driving or misfires
- The engine is difficult to start
- The starter motor does not turn, or turns but the engine does not start
General guidance for car owners. Diagnosis on the car can point to a different cause.