VOLVO
CEM-8F16 - Xenon lamp left. Signal too low
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
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 central electronic module (CEM) has registered that the signal from the left xenon lamp is too low. The fault is only checked with the ignition on and sufficient battery voltage, and it can come from a signal wire shorted to ground or from an actuator motor in the lamp housing that has jammed or been damaged.
Possible causes
- Signal wire short-circuited to ground
- The motor that moves the xenon lamp has seized
- Faulty or broken motor that moves the xenon lamp
What you can do
- 1Check the battery: it should be charged and the terminals tight, because the fault is only tested when the battery voltage is sufficient
- 2With the ignition on, switch between low and high beam: if the lamp does not change, the fault is permanent; if it changes, the fault has occurred before
- 3Use a multimeter to check that the signal wire to the left lamp has no contact with ground (the body) with the ignition off
- 4If you have a diagnostic tool, activate the actuator motor in the left headlamp and check that it moves
- 5If the fault remains after these checks, have a workshop replace the left headlamp housing
Symptoms you may notice4
- The low beam is constantly lit
- The high beam is constantly lit
- Road surface lighting does not work
- Headlamp aim is wrong or the height adjustment does not work
What the fault can affect1
- The shortest beam range is used
General guidance for car owners. Diagnosis on the car can point to a different cause.