VOLVO
ECM-801C - System relay. Signal too high
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (9)
- Volvo C30 (2007–2013)2007Engine B5254T3 only
- Volvo C30 (2007–2013)2008–2013Engine B5254T7 only
- Volvo C70 (2006–2013)2006–2007Engine B5254T3 only
- Volvo C70 (2006–2013)2008–2013Engine B5254T7 only
- Volvo S40 (2004–2013)2005–2007Engine B5254T3 only
- Volvo S40 (2004–2013)2008Engine B5254T3, B5254T7 only
- Volvo S40 (2004–2013)2009–2012Engine B5254T7 only
- Volvo V50 (2004–2013)2005–2007Engine B5254T3 only
- Volvo V50 (2004–2013)2008–2012Engine B5254T7 only
What does this fault code mean?
The engine control module registers that the voltage on the system relay signal wire is too high. The cause may be a signal wire shorted to supply voltage or a damaged system relay, and the engine then does not start.
Possible causes
- Signal wire shorted to supply voltage
- Damaged system relay
What you can do
- 1Read and note the code, clear it and road test to see whether it returns
- 2Inspect the signal wire to the system relay where it may have touched a live wire, and check for chafing and pinching
- 3Using a multimeter, check that the signal wire does not carry voltage where it should not
- 4If no fault is found, have a workshop try a new system relay
Symptoms you may notice1
- The engine does not start
General guidance for car owners. Diagnosis on the car can point to a different cause.