VOLVO
CEM-B104421 - Rear Axle Sensor. General Signal Failures. Signal too low
System
Sentral elektronikk (CEM)
Volvo-modeller feilkoden gjelder for
Gjelder følgende modeller:
9 modellerS60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
Hva betyr feilkoden?
The central electronic module (CEM) reads the rear axle level sensor, which measures the height at the rear of the car and is used to adjust the headlights. The signal is lower than expected compared with the supply voltage, which the CEM treats as a fault. The headlight setting then cannot be determined correctly.
Mulige årsaker
- The supply to the sensor is shorted to ground
- The signal cable to the rear sensor is shorted to ground
- Oxidized or loose connections at the sensor connector
- Open circuit in the supply lead to the sensor
- Damaged sensor
Hva du kan gjøre
- 1Read off and note the code, clear it and carry out a short test drive to see whether it returns
- 2Check that the fuses for the headlight level control are intact
- 3Check the connector at the rear sensor: it should be fully engaged and free from corrosion, and the cable should not be chafed or pinched
- 4Use a multimeter (ignition off, connector unplugged) to check that the supply lead has no connection to ground
- 5With a diagnostic tool, watch the rear sensor value in live data as the rear is pressed: it should change smoothly, not stay at its lowest value
- 6If the fault remains, have a workshop check the sensor and the wiring to it
Symptomer du kan merke2
- Headlight side adjustment does not follow the steering wheel
- Headlight height adjustment does not work or is set wrongly
Hva feilen kan påvirke2
- The headlight beam stays at a fixed level instead of being adjusted
- Side adjustment stays fixed straight ahead
Generell veiledning for bileiere. Feilsøking på bilen kan peke på en annen årsak.