VOLVO
ECM-C1A9679 - Brake Light Switch. Mechanical Failures. Mechanical linkage failure
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
12 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), S60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V50 (2004–2013), V60 (2011–), V70 (2008–), XC60 (2009–), XC70 (2008–)
Show models by year and engine (40)
- Volvo C30 (2007–2013)2011–2013Engine D5204T, D5204T5 only
- Volvo C70 (2006–2013)2011Engine D5204T, D5204T5 only
- Volvo C70 (2006–2013)2012–2013All engines except: B5254T7
- Volvo S40 (2004–2013)2011–2012Engine D5204T, D5204T5 only
- Volvo S60 (2011–)2011Engine D5204T2, D5244T10 only
- Volvo S60 (2011–)2012Engine D5204T3, D5244T11, D5244T15 only
- Volvo S60 (2011–)2013–2014Engine D5204T3, D5204T7, D5244T11, D5244T15 only
- Volvo S60 (2011–)2015Engine D5204T3, D5204T7, D5244T11, D5244T15, D5244T23 only
- Volvo S80 (2007–)2009Engine D5244T10 only
- Volvo S80 (2007–)2010Engine D5244T10, D5244T14, D5244T19 only
- Volvo S80 (2007–)2011Engine D5204T2, D5244T10 only
- Volvo S80 (2007–)2012Engine D5204T3, D5244T11, D5244T15 only
- Volvo S80 (2007–)2013–2014Engine D5204T3, D5204T7, D5244T11, D5244T15 only
- Volvo S80 (2007–)2015Engine D5204T3, D5244T15 only
- Volvo V40 (2013–)2013–2014Engine D5204T4, D5204T6 only
- Volvo V40 (2013–)2015Engine D5204T6 only
- Volvo V40 Cross Country (2013–)2013–2014Engine D5204T4, D5204T6 only
- Volvo V40 Cross Country (2013–)2015Engine D5204T6 only
- Volvo V50 (2004–2013)2011–2012Engine D5204T, D5204T5 only
- Volvo V60 (2011–)2011Engine D5204T2, D5244T10 only
- Volvo V60 (2011–)2012Engine D5204T3, D5244T11, D5244T15 only
- Volvo V60 (2011–)2013Engine D5204T3, D5204T7, D5244T11, D5244T15, D5244T17 only
- Volvo V60 (2011–)2014Engine D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17 only
- Volvo V60 (2011–)2015Engine D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17, D5244T23 only
- Volvo V70 (2008–)2009Engine D5244T10 only
- Volvo V70 (2008–)2010Engine D5244T10, D5244T14, D5244T19 only
- Volvo V70 (2008–)2011Engine D5204T2, D5244T10 only
- Volvo V70 (2008–)2012Engine D5204T3, D5244T11, D5244T15 only
- Volvo V70 (2008–)2013Engine D5204T3, D5204T7, D5244T11, D5244T15, D5244T17 only
- Volvo V70 (2008–)2014–2015Engine D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17 only
- Volvo XC60 (2009–)2010Engine D5244T10, D5244T14, D5244T16 only
- Volvo XC60 (2009–)2011Engine D5204T2, D5244T10, D5244T16 only
- Volvo XC60 (2009–)2012Engine D5204T3, D5244T11, D5244T15, D5244T17 only
- Volvo XC60 (2009–)2013All engines except: B4204T7, B6304T4, B6324S4, B6324S5
- Volvo XC60 (2009–)2014Engine D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17 only
- Volvo XC60 (2009–)2015Engine D5204T3, D5204T7, D5244T11, D5244T12, D5244T15, D5244T17, D5244T23 only
- Volvo XC70 (2008–)2010Engine D5244T10, D5244T14, D5244T16 only
- Volvo XC70 (2008–)2011Engine D5204T2, D5244T10, D5244T16 only
- Volvo XC70 (2008–)2012–2013All engines except: B6304T4, B6324S4, B6324S5
- Volvo XC70 (2008–)2014–2015Engine D5204T3, D5244T11, D5244T12, D5244T15, D5244T17 only
What does this fault code mean?
Although the code is named a mechanical linkage failure, it concerns the signal from the brake light switch at the brake pedal. The signal shows that the pedal is pressed while the brake pressure is low as the car accelerates. The fault can stop the cruise control from engaging and stop the brake lights from working.
Possible causes
- Contact resistance or oxidation in the connections to the brake light switch
- Short circuit to supply voltage
- Short circuit to ground
- Open circuit in the wire to the brake light switch
What you can do
- 1Check that the fuses are intact. Their locations are in the owner's manual
- 2Check that the brake lights come on and go off when the pedal is pressed and released
- 3Check that the connector at the brake light switch is firmly seated and clean
- 4Use a multimeter to check that the wire to the brake light switch has no contact with ground or supply voltage with the connectors disconnected
- 5If you have a diagnostic tool: read the brake light switch status in live data and check that the value changes when you press and release the brake
- 6The fault concerns the braking system. If the pedal or brakes feel abnormal, do not drive the car; have a workshop check it
Symptoms you may notice2
- The cruise control does not engage
- The tail lights and brake lights do not work
General guidance for car owners. Diagnosis on the car can point to a different cause.