VOLVO
UEM-0090 - Rear view mirror, display. 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:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
What does this fault code mean?
The upper electronic module (UEM) monitors the supply voltage to the five LEDs in the display in the interior rear view mirror. The code is set when the supply to these LEDs is too low. The cause is that the supply wire is short-circuited to ground. The SRS warning lamp can then light.
Possible causes
- The rear view mirror display LEDs have a supply line shorted to ground
What you can do
- 1Have a workshop check the wire to the display in the interior rear view mirror.
- 2Have a workshop measure the supply wire to the display for contact with ground (the bodywork).
- 3Read off the code, clear it and check whether it returns.
- 4If the SRS warning lamp is lit, have a workshop check the airbag system.
- 5If the fault remains, have a workshop repair the wire and read out the programmed data before the upper electronic module is replaced.
Symptoms you may notice1
- The SRS warning lamp is lit
General guidance for car owners. Diagnosis on the car can point to a different cause.