VOLVO
ECM-843B - Starter motor relay. Open
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)2006–2007Engine B5254T3 only
- Volvo S40 (2004–2013)2008Engine B5254T3, B5254T7 only
- Volvo S40 (2004–2013)2009–2012Engine B5254T7 only
- Volvo V50 (2004–2013)2006–2007Engine B5254T3 only
- Volvo V50 (2004–2013)2008–2012Engine B5254T7 only
What does this fault code mean?
The ECM monitors the starter motor relay signal that runs through its ground wire. The code is set if the signal is missing or faulty. The check only starts after the engine has been started, so the fault can only be detected once the engine is running and the conditions are met. The cause may be an open circuit in the ground wire between the control module and the starter relay, or an internal fault in the relay.
Possible causes
- Open circuit in the ground wire between the engine control module (ECM) and the starter relay
- Internal fault in the starter relay
What you can do
- 1Read the code, clear it and road test the car to see whether it comes back
- 2With the ignition off, check the connections and wiring between the control module and the starter relay for breaks and loose fit
- 3Use a multimeter to check that the ground wire to the starter relay has no break to the body
- 4Check that the starter relay is firmly seated and that its contacts are free from oxidation
- 5If the fault remains after these checks, have a workshop try a new starter relay
Symptoms you may notice1
- The starter motor does not operate
General guidance for car owners. Diagnosis on the car can point to a different cause.