VOLVO
ECM-U1A0400 - Vehicle Speed CAN 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–)
What does this fault code mean?
The engine control module (ECM) monitors the speed signal that arrives over CAN. The code is set when the ECM gets a signal that data from the BCM or the TCM cannot be trusted, or when the speed signal over CAN is faulty. The fault therefore lies in the speed data from the BCM or the TCM.
Possible causes
- The fault is in the brake control module (BCM)
- The fault is in the transmission control module (TCM)
What you can do
- 1Read the fault codes in the brake control module (BCM) and remedy them first.
- 2Read the fault codes in the transmission control module (TCM) and troubleshoot according to them.
- 3Check that the fuses are intact and that the connectors to the BCM and TCM are secure and clean.
- 4Do not work on the brake system yourself. Have a workshop check the BCM if the code returns.
Symptoms you may notice3
- The check engine lamp lights up or behaves abnormally
- Warning symbol and message in the display
- The emissions warning lamp is lit
General guidance for car owners. Diagnosis on the car can point to a different cause.