VOLVO
ECM-P039400 - Camshaft Position Sensor B Circuit Intermittent (Bank 2). General Failure Information. No sub type information
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
1 modelS80 (2007–)
Show models by year and engine (1)
What does this fault code mean?
The fault is intermittent, which means it has occurred at an earlier time but may not be present at the moment. The engine control module (ECM) reads the teeth of a toothed wheel on the camshaft via the camshaft position sensor for the exhaust camshaft on bank 2. The fault is set when the control module detects too few segments over a certain number of crankshaft revolutions.
Possible causes
- Contact resistance or oxidation in the connections
- Open circuit in the signal cable
- Signal cable short-circuited to supply voltage
- Signal cable short-circuited to ground
- Camshaft position sensor fitted incorrectly
- Damaged camshaft position sensor
What you can do
- 1If you have a diagnostic tool, read the fault status after the engine has run: Fault found means a permanent fault, No fault found means it is not active now
- 2Check that the camshaft position sensor is firmly fitted and in the correct position
- 3Check the connections to the camshaft position sensor for contact resistance and oxidation
- 4Check the wiring to the camshaft position sensor for chafing and pinching
- 5Measure with a multimeter that the signal cable has no contact with ground or supply voltage, and that the supply and ground wires have no open circuit
- 6After a repair, check that the diagnosis completes and that the fault status shows No fault found
Symptoms you may notice1
- The Check engine (malfunction indicator) light comes on or behaves abnormally
What the fault can affect2
- The control module uses the signal from the engine speed sensor instead
- The variable valve timing (VVT) control is blocked
General guidance for car owners. Diagnosis on the car can point to a different cause.