Error code 6B: LIN Bus no response, Passenger Mirror

Hi Everyone,

I've got a mirror problem with my 2004 325ci coupe and searched through all related problems on this forum and others but none are the same as my problem.

My mirrors were working fine with no problems until I disconnected the battery to install the BMW Performance Strut Brace.

After reconnecting the Battery:
When i select the mirror switch to the driver's side, I can control both mirrors but the strange part is that if i adjust the driver's mirror up/down, the passenger mirror moves left/right simultaneously. If I adjust the driver's mirror left/right, the passenger mirror moves up/down simultaneously.

i have also lost the parking tilt down function when the switch is selected to the Driver's side.

I scanned the OBD for fault codes and got this:

CODE001: 6B LIN Bus: No Response, Passenger Mirror

Anybody know what's causing the lack of signal through the LIN Bus? I've checked fuses and they are fine.

Also, I don't think the mirror motors have failed as they were working fine before i disconnected the battery. and as i mentioned above, then the switch is selected on the driver's side both mirrors move.

Could this just be a faulty switch?

Any help is much appreciated!

Thanks.

Did you use one of those memory savers that plug into the cigarette lighter?

No I didn't.

does this mean i need to reprogram my GM5 Module?

by the way, in case it helps, my mirrors are not the old in type but they have memory with front seats and are heated.

Originally Posted by Infini

No I didn't.

does this mean i need to reprogram my GM5 Module?

No. I thought perhaps the slightly lower voltage output from the saver may have caused a glitch. They normally only put out 9v. These cars are known to do weird things when the system voltage goes awry (such as a battery going bad).

I don't believe any reprograming is necessary. My only other thought is to disconnect the battery again (~20min) and reconnect in hopes of resetting the module.

oh I see. I've tried disconnecting the battery again but i don't think i left it disconnected for 20 min. I'll try this again and maybe get the battery tested and see if this solves the problem.

Thanks mr bean for your input!

Hi all, I'm a new owner and a new forum member. My 05 325xit has the same issue as the original post. When the mirror switch is moved left, both mirrors adjust simultaneously, although in different directions. When the mirror switch is moved right, it's dead. Infini, or anyone else - can you help? I have already been to the very reputable BMW mechanic in town (not the dealer) and they couldn't help. Thanks.

ok sorry it's been a few months, I've tried disconnecting the battery again, both terminals. this time i nearly lost half the car's electronics. It was only when i was checking all the fuses that all the electronics came back even though none of the fuses were blown.

Sadly, my mirror issue remains..... I'm running out of options and i know it can't possibly be the mirror itself.

Nothing has shorted so i don't understand how disconnecting the battery the first time caused the LIN bus to lose connection to one mirror.

How did you resolve this? I have the same issue with both side mirrors unresponsive after the battery was disconnected.

I still have not been able to resolve this.

now both my mirrors are unresponsive. Occasionally, i do re-gain functionality with the right side mirror (with the left moving simultaneously).

I have purchased one mirror module but Have not replaced the driver's side with it as I may try the mirror switch first.

I am having a similar problem with my '04 330xi. I disconnected the battery for a couple hours while I was fixing the driver door's window regulator (plastic clip broke). After reconnecting the battery, I have been unable to control the mirrors with the toggle. Now whenever I turn the car off, the mirror on the side where the toggle is set to control tilts the mirror into a straight up position. (This would be helpful if I was trying to keep an eye on the airplane in the lane behind me, but not so much for seeing other cars.) I have tried replacing the switch itself, but no luck. My mechanic told me I need to take the car to the dealership to have the computer reprogrammed. The guy at the dealership does not think this is the problem from what I described, but wants $125 to tell me for sure.

Glad to know I'm not alone, but finding a fix would be even better!

UPDATE:
Tried completely disconnecting the battery (+ and - terminals) and left overnight. Still not fixed, but at least no new problems like others have experienced.

My guess would have to be either the mirror switch or the mitror module. Since youve already tried replacing the switch, maybe try the mirror module. Im just not sure which side you should replace first.
Since both my mirrors move in perpendicular directions only when the mirror switch shifted to the drivers side, im not sure which of my mirror modules could be faulty. But im waiting for my mirror switch to arrive and ill replace that first.

Also, upon reading Mr_Bean's post earlier, I'm beginning to think that this could all be related to the battery. Even though the battery could be reading at the correct voltage, i get the feeling that it is beginning to wear out. I still have the original battery and if replacing the mirror modules and mirror switch don't resolve this problem, then i will try to replace the battery next.

We had been living with this mirror problem for a year, where moving the mirror controller made both side mirrors move simultaneously but perpendicularly, i.e. one moved up/down and the other move left/right and at the same time. We just replaced the battery and the problem went away. Now they work fine. We had the original battery in our '05 with 60k and I think it had been wearing down for a while.