[Nick54]

I'm currently chasing problem with my rear headlight level sensor. The headlights constantly adjust up and down even while the car is stationary. I brought the car into the dealership and they diagnosed it as being a faulty sensor. I had the sensor replaced and it did nothing. also when reading the codes, even after clearing I always get code 9CB4 for a faulty rear sensor. After doing some research, I'm now thinking it's either a fuse or a bad frm.

would any of you know the location of this fuse if it exists? also how can I test if the fuse is bad?

some things to note:
- new AGM battery installed just before this problem occured I did code it properly
- new engine ground was installed by the dealership
- new gas pedal was installed after car went into limp mode

2010 e92 335i xdrive N54 manual with adaptive xenon headlights

if any of you has experienced this before I would love to know how you resolved this!

any help is much appreciated!

[Nick54]

Originally Posted by Nick54

I'm currently chasing problem with my rear headlight level sensor. The headlights constantly adjust up and down even while the car is stationary. I brought the car into the dealership and they diagnosed it as being a faulty sensor. I had the sensor replaced and it did nothing. also when reading the codes, even after clearing I always get code 9CB4 for a faulty rear sensor. After doing some research, I'm now thinking it's either a fuse or a bad frm.

would any of you know the location of this fuse if it exists? also how can I test if the fuse is bad?

some things to note:
- new AGM battery installed just before this problem occured I did code it properly
- new engine ground was installed by the dealership
- new gas pedal was installed after car went into limp mode

2010 e92 335i xdrive N54 manual with adaptive xenon headlights

if any of you has experienced this before I would love to know how you resolved this!

any help is much appreciated!

anyone have some info?

[opjose]

In your shoes I would check the wiring and receptacles/connectors to the rear sensor.

That should be the most likely culprit after the sensor itself.

[Nick54]

Originally Posted by opjose

In your shoes I would check the wiring and receptacles/connectors to the rear sensor.

That should be the most likely culprit after the sensor itself.

thank you very much for the reply. I haven't been getting any good information and it's getting super frustrating. finally have a place to look!

[nsjames]

mine has had an error forever, and now I'm looking at diagrams in the newtis.

so lets collaborate.
I'm going to go poke around and see what I get at it's connector in a little while after I better understand the diagrams.

[nsjames]

so I asked the FRM what the sensor voltage was in INPA and I get 5V when it's unplugged and 0V when it's plugged in.

which seems backwards, but ok.

I put a meter on the connector for the reference voltage and only got 2.6V though, and that seems odd.

[Nick54]

Originally Posted by nsjames

so I asked the FRM what the sensor voltage was in INPA and I get 5V when it's unplugged and 0V when it's plugged in.

which seems backwards, but ok.

I put a meter on the connector for the reference voltage and only got 2.6V though, and that seems odd.

I'm still looking to fix this problem as well. I know the mechanic broke my connector so I'm trying to replace that and hopefully it solves my problem. have you had any luck?

[nsjames]

well I'm mostly convinced that I have an actual sensor issue.

but I haven't yet ordered a new one.

[Nick54]

Originally Posted by nsjames

well I'm mostly convinced that I have an actual sensor issue.

but I haven't yet ordered a new one.

try that out first.. I replaced mine and it wasn't working at all.. I unplugged and replugged it yesterday and it seems to be working fine now. I'm guessing the connector wasnt fully seated the first time. hope that helps!