MJJ
Senior Member
- Joined
- Jan 15, 2020
- Messages
- 74
- Reaction score
- 80
- Location
- Wiltshire
- Your Mercedes
- '09 S211 E220 Cdi manual - 216k miles and counting
Afternoon all,
Sometime in the last couple of weeks, the headlamp aim on my 2009 E220 estate (with Xenons) has started pointing very low. The lights do their normal up/down travel validation routine on start-up, then set themselves to a very low aim - meaning only 3-4 metres in front on the car are properly illuminated.
What I have checked:
- The bulbs are securely seated in their sockets as normal.
- The headlight assemblies themselves are both securely, and correctly mounted.
- Both front and rear axle ride height sensors appear to be mounted correctly compared to photos on the web, and nothing is mechanically broken.
- Looking at Live Data on Carsoft, the ride height sensor voltage changes (in what seems a sensible, correct way to me) when the ride height of the car changes.
- There are no error codes stored anywhere that I can see related to headlights.
- Carsoft displays a suspension compression value in millimeters as part of live data, but I don't know where it gets this from. This mm value seems very wrong to me, reading 31mm compression (31mm front, 4mm rear) when the car is sitting level and static,
- This same Carsoft mm measurement also changes in the opposite way to expected on both axle sensors - i.e. compressing the suspension physically by pushing down on the corner *reduces* the compression value in mm. The voltage change seems sensible and linear, just not the mm equivalent.
Anyone got any ideas?
Martin.
Sometime in the last couple of weeks, the headlamp aim on my 2009 E220 estate (with Xenons) has started pointing very low. The lights do their normal up/down travel validation routine on start-up, then set themselves to a very low aim - meaning only 3-4 metres in front on the car are properly illuminated.
What I have checked:
- The bulbs are securely seated in their sockets as normal.
- The headlight assemblies themselves are both securely, and correctly mounted.
- Both front and rear axle ride height sensors appear to be mounted correctly compared to photos on the web, and nothing is mechanically broken.
- Looking at Live Data on Carsoft, the ride height sensor voltage changes (in what seems a sensible, correct way to me) when the ride height of the car changes.
- There are no error codes stored anywhere that I can see related to headlights.
- Carsoft displays a suspension compression value in millimeters as part of live data, but I don't know where it gets this from. This mm value seems very wrong to me, reading 31mm compression (31mm front, 4mm rear) when the car is sitting level and static,
- This same Carsoft mm measurement also changes in the opposite way to expected on both axle sensors - i.e. compressing the suspension physically by pushing down on the corner *reduces* the compression value in mm. The voltage change seems sensible and linear, just not the mm equivalent.
Anyone got any ideas?
Martin.
