VOLVO
SUM-0031 - Position sensor, suspension left rear. Signal too low
System
Suspension Module (SUM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007)
Show models by year and engine (7)
What does this fault code mean?
The signal from the position sensor at the left rear wheel is too low. The sensor is mounted on a bracket in the body and reports the position of the rear wheel to the suspension control module.
Possible causes
- Ground fault on the signal wire running from the position sensor
- A break, or a ground fault, in the supply wire to the position sensor
- Poor contact in the connections
- Defective position sensor
What you can do
- 1Check the connectors at the position sensor and at the suspension control module for loose or oxidised connections
- 2Check the wiring to the position sensor at the left rear wheel for chafing and crushed sections
- 3If you have a diagnostic tool: read live data for the left rear position sensor and check that the value follows the rear wheel as it moves up and down
- 4Check that the suspension system fuses are intact; the owner's manual shows where they are
- 5If the wiring is intact, the position sensor is probably defective. Have a workshop replace it
Symptoms you may notice3
- The general warning lamp lights
- Message in the display
- Four-C does not work
What the fault can affect1
- Four-C control is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.