VOLVO
ECM-8030 - Secondary battery relay. Temperature too high
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
3 modelsC30 (2007–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
The secondary battery relay links the back-up battery to the car's electrics while the starter turns and the engine is restarted after an auto-stop, and the engine control module monitors it. The too-high temperature fault is most likely caused by the relay being overloaded. Automatic start and stop of the engine then does not work. The fault applies to the C30, S40 (04-) and V50.
Possible causes
- Loose connection or oxidation in the connector
- Short circuit in the connections
- Damaged secondary battery relay
What you can do
- 1Check that the fuses are intact
- 2Test the automatic start and stop function at idle to see whether it works
- 3Check the connectors at the secondary battery relay for looseness, contact resistance and oxidation
- 4Look for chafed or shorted wiring to the relay
- 5If the fault remains, have a workshop with diagnostic equipment check the secondary battery relay
Symptoms you may notice1
- Automatic engine start and stop does not work, both while driving and at idle
What the fault can affect1
- The automatic engine start and stop function is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.