BMW 540I E39 rear view inside auto-dim mirror problems, no replacement found

[Rudy 12]

I have 2000 BMW 540I E39. I am in situation when I have replaced several times the inside auto-dim rear view mirror without success.

The original auto-dim mirror failed. The head lights of the cars following us had multiple, bright, line-like horizontal reflections above and below them. We could not use the car at night. We have replaced the original mirror with $30 junk yard mirror which shown much shorter horizontal line reflections but the car was still unusable at night. Then we purchased brand new BMW OEM mirror for $750. That mirror worked exactly the same as the junk yard mirror and car is still not usable at night.
I have checked the fuse and it was OK.

Did anyone go through similar problem and found a solution?

Is BMW aware of this problem?

Any information you have would be appreciated.

[demetk]

I had a plain mirror in my touring and replaced it with an e34 auto-dim mirror and it works great with no weird lines like you're describing.

[Samsam15]

The mirror is quite self contained, the reversing signal is the only outside input. I have never seen a similar fault, does it dim? You can test it by covering the photocell on the back and shining some light on the front.

[Rudy 12]

Hi Sam, the mirror will lighten when the car is put into reverse. As far as I can tell it is not dimming, could be it is dimming partially. The last mirror is brand new OEM BMW and it is doing exactly what the junk yard mirror had been doing. I will try again to test it the way you suggest. Your kind help is appreciated.

[Rudy 12]

Hi Sam,
I am going to do some testing tonight. Thanks.

[Aubergine]

Hi Rudy,

So, different generations of mirrors have different dimming capacities. Those originally fitted to E39s were good, but the E9X generation mirrors tend to dim much more significantly. If you past the part number or a photo of the mirrors you are using it would help identify.

Additionally, you can always swap to a manual dimming mirror off of a base model car. It will look the same but you turn the 'clown nose' at the bottom of the mirror. This may provide dimming more like you are used to in other cars.

[Rudy 12]

Hi Aubergine,

The original mirror was BMW part number 5116 823 6774. It was replaced by by new OEM BMW light 5116 913 4416, BMW recommended replacement. I tested the new mirror last night and it would not un-dim when put in the reverse. I could see no change in dimming when covering the photocells one after the other, when our other car was parked behind the 540i. I tried the suggestion from Sam Sam and the new mirror is not reacting at all. The junk yard mirror( part number unknown), did un-dim when in reverse but the lines were still present. It almost looks like there is no power fed into the mirror.

I believe the 540I mirror has rain sensing and alarm functions in it and is probably different from 528 mirrors. Do you think the manual mirror would fit?
Thanks for your post

[Asbradley21]

A manual mirror will drop right in place. You will just have to swap your RLS sensor-fitting plastic shroud onto it.

Edited to add: The manual dimming mirror has a much greater dimming capacity than the auto dimming mirror.

[Samsam15]

Here is the pinout and diagram, https://www.newtis.info/tisv2/a/en/e39-540i-lim/ZVeyrUG https://www.newtis.info/tisv2/a/en/e...irrors/aHlRW8K, you should have switched power on pin 3 (green/white wire), always on power at pin 8, ground at pin 10 (brown/black) and pin 10 is reversing signal, not sure if this is switched high.

[Rudy 12]

Thanks much Sam

- - - Updated - - -

Thanks Brad

[E39 Newbie]

Slightly off topic and out of left field, but a shout out to Aubergine. I had no idea that the stupid clown nose TURNED!! I was always readjusting the d**n mirror and hating it. I suppose if I took the time to read the owner's manual I might learn a lot. But who reads instructions??

[Rudy 12]

Gentlemen, thank you for your responses.

The mystery was solved by the local BMW dealer. It has nothing to do with the mirror. The light from headlights following my car has to go through the rear window with defroster and attached dark tint plastic film. With time the heat in back window distorts the tint plastics film and creates strange reflections that appear like horizontal lines in the mirror. The reflections are spaced same as the defroster conductors. Replacement of the plastic tint solved the problem.

Regards,
Rudy

[Aubergine]

Slightly off topic and out of left field, but a shout out to Aubergine. I had no idea that the stupid clown nose TURNED!! I was always readjusting the d**n mirror and hating it. I suppose if I took the time to read the owner's manual I might learn a lot. But who reads instructions??

Haha, Happy to help! BMW really snuck that one in there.

Gentlemen, thank you for your responses.

The mystery was solved by the local BMW dealer. It has nothing to do with the mirror. The light from headlights following my car has to go through the rear window with defroster and attached dark tint plastic film. With time the heat in back window distorts the tint plastics film and creates strange reflections that appear like horizontal lines in the mirror. The reflections are spaced same as the defroster conductors. Replacement of the plastic tint solved the problem.

Regards,
Rudy

Ahhh! I didn't even think to ask about your tint situation. Glad you were able to resolve it!

[BimmrMeUpSnotty]

E39noobster, if you want a auto dimming mirror, Send me a pm, I have a bunch, even a couple or so with the compass, they just need to be plugged in to the harness that your car already has, plug n play. The compass may need to be recalibrate which involves driving around in circles in an empty parking lot for about a minute or so.

[StephenVA]

Oh I want compass.....

[BimmrMeUpSnotty]

Oh I want compass.....

You just want another excuse to do some donuts.

- - - Updated - - -

Seriously, Stephen, lemme know if you want one. Free of charge, but shipping from Alexandria to Arlington, fiddy buks..... lol

[StephenVA]

Ohhhh Fresh Donuts. Need this and a CheeseSteak sub. This hiding in place sucks....

[Bmwe39528i1998]

Here is the pinout and diagram, https://www.newtis.info/tisv2/a/en/e39-540i-lim/ZVeyrUG https://www.newtis.info/tisv2/a/en/e...irrors/aHlRW8K, you should have switched power on pin 3 (green/white wire), always on power at pin 8, ground at pin 10 (brown/black) and pin 10 is reversing signal, not sure if this is switched high.

Looking at the pinout and the wiring diagram.
I dont see pins 2, 8 and 9 on the wiring diagram.
I've already installed electrochromatic auto dim side mirrors and a compass rearview mirror with garage buttons.
The rearview mirror connector is provisioned for 10 wires, however I only have a couple wires there. I'd like to add all the other wires for full functionality. Just need to know where each wire goes.

- - - Updated - - -

https://www.newtis.info/tisv2/a/en/e39-540i-lim/a7BxfZt

[Samsam15]

Pin 2 would not be used on most cars as it's for the IR remote, pin 8 and 9 are on this diagram https://www.newtis.info/tisv2/a/en/e...bus/1VnZ70ARbj.