VOLVO
SUM-C1A0529 - Left Rear Height Sensor. General Electrical Failures. Signal plausibility failure
System
Suspension Module (SUM)
Volvo models this fault code applies to
Applies to the following models:
7 modelsS60 (2011–), S80 (2007–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The height sensor at the left rear wheel gives a signal with a voltage outside the permitted range. The SUM interprets this as a fault, and when the signal is implausible the Four-C function is switched off.
Possible causes
- Contact resistance or oxidation in the connectors
- A break in the signal wire between the height sensor and the module
- Damaged height sensor
What you can do
- 1Read and note the code, clear it and road test the car to see whether it returns
- 2Check the connector at the height sensor at the left rear wheel: it should be firm and free from oxidation
- 3Inspect the cable from the height sensor for breaks, chafing and loose clips, especially where it moves with the suspension
- 4If you have a multimeter, check that the signal cable has no open circuit
- 5With a diagnostic tool, watch the left rear height sensor value in live data as the rear of the car moves; it should change smoothly
- 6If the fault returns, have a workshop with diagnostic equipment check the height sensor and the wiring
Symptoms you may notice2
- A message appears in the information display
- The Four-C function does not work
What the fault can affect1
- The Four-C function is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.