VOLVO
ECM-1912 - Reverse Lamp Control Circuit 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)
Show models by year and engine (9)
- Volvo C30 (2007–2013)2008–2009Engine B4184S11, B4184S8, B4204S3 only
- Volvo C30 (2007–2013)2010Engine B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo C30 (2007–2013)2011–2013Engine B4204S3, B4204S4 only
- Volvo S40 (2004–2013)2008–2009Engine B4184S11, B4184S8, B4204S3 only
- Volvo S40 (2004–2013)2010Engine B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo S40 (2004–2013)2011–2012Engine B4204S3, B4204S4 only
- Volvo V50 (2004–2013)2008–2009Engine B4184S11, B4184S8, B4204S3 only
- Volvo V50 (2004–2013)2010Engine B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo V50 (2004–2013)2011–2012Engine B4204S3, B4204S4 only
What does this fault code mean?
The engine control module (ECM) monitors the signal for the reversing lamp. If the signal is faulty the code is set, and a typical sign is that the reversing lamp stays on all the time. The fault can come from an open circuit or a short to ground or supply voltage in the wire, or from poor contact in the connections.
Possible causes
- Open circuit in the wire
- Wire short-circuited to ground
- Wire short-circuited to supply voltage
- Contact resistance or oxidation in the connections
- Open or short circuit in the connections
What you can do
- 1Read and clear the fault code and check whether it returns
- 2Check that the fuse for the reversing lamps is intact
- 3Check the connectors at the reversing lamp and in the rear wiring harness for play, oxidation and corrosion
- 4Use a multimeter to check that the wire to the reversing lamp has no open circuit and is not short-circuited to ground or supply voltage
- 5If you have a diagnostic tool, follow the reversing lamp state in live data when you select reverse and back out of it
Symptoms you may notice1
- The reversing lamp is lit all the time
General guidance for car owners. Diagnosis on the car can point to a different cause.