VOLVO
UEM-0030 - Rear left reading lamp. Signal too low
System
Upper Electronic Module (UEM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
3 modelsV70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (3)
What does this fault code mean?
The code is set when the control module detects a bad control signal coming from the lamp circuit while the rear left reading lamp is lit and the front left reading lamp is off. The fault comes from the signal wire being short-circuited to ground, or from a break that comes and goes in it.
Possible causes
- The signal wire to the rear left reading lamp is short-circuited to ground
- A break in the signal wire that comes and goes
What you can do
- 1Check that the bulb in the rear left reading lamp is intact.
- 2Read off the code, clear it and check whether it returns.
- 3Check that the connectors at the upper electronic module and at the rear reading lamp are firmly seated and not corroded.
- 4Use a multimeter to check that the wire running from the upper electronic module to the rear reading lamp has no contact with ground.
- 5Look for pinched or chafed spots that can cause an intermittent break, and replace the wire if a fault is found.
Symptoms you may notice1
- Passenger compartment lighting does not work
What the fault can affect1
- The rear left reading lamp goes out
General guidance for car owners. Diagnosis on the car can point to a different cause.