VOLVO
ECM-P1A0500 - Desired Engine Speed Signal. General Failure Information. No sub type information
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsS80 (2007–), V70 (2008–)
Show models by year and engine (2)
What does this fault code mean?
Although the code is named desired engine speed signal, it applies when the speed signal from the transmission control module (TCM) is faulty. The TCM sends a fault message to the engine control module (ECM), which stores a code, while the code for the speed sensor signal is stored in the TCM. The cause should therefore be looked for in the transmission control module.
Possible causes
- Fault in the transmission control module (TCM)
- Fault in the speed sensor signal to the transmission control module (TCM)
What you can do
- 1Read off the trouble codes in the transmission control module (TCM) and remedy them first, as the code in the engine control module is a following fault
- 2Clear the code in the engine control module only once the root fault in the transmission control module has been remedied and its trouble code has been cleared
- 3Check that the connectors to the transmission control module are secure and free from oxidation
- 4If you have a diagnostic tool: compare the speed value in the transmission control module's live data with the speedometer during a test drive
Symptoms you may notice1
- No noticeable symptoms for the driver
General guidance for car owners. Diagnosis on the car can point to a different cause.