VOLVO
ECM-P050065 - Vehicle Speed Sensor A. Algorithm Based Failures. Signal has too few transitions / events
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
3 modelsS60 (2011–), S80 (2007–), V70 (2008–)
Show models by year and engine (9)
- 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
What does this fault code mean?
The code concerns the speed signal, which has too few transitions to be reliable. The fault may lie in the CAN communication, in the wiring between the control modules, or in the brake control module or the engine control module.
Possible causes
- Contact resistance in the CAN connections
- Break in one or both CAN wires
- One or both signal wires touching ground, supply voltage or the other wire
- Damaged brake control module (BCM)
- Damaged engine control module (ECM)
What you can do
- 1If you have a diagnostic tool, read the fault codes in the brake control module and the engine control module, and remedy them first
- 2Check that the CAN connectors are secure and free from oxidation
- 3Look for chafing or pinch damage on the CAN wires and use a multimeter to check that they have no break
- 4The brake system is safety-critical: have a workshop check the brake control module. Do not work on the brake system yourself
- 5Clear the fault code once the fault has been remedied, then road test
Symptoms you may notice1
- The malfunction indicator lamp (MIL) lights up
What the fault can affect1
- the brake module speed signal is replaced by a fixed value
General guidance for car owners. Diagnosis on the car can point to a different cause.