Z4-forum.com

Hi all,

I hope this is useful to someone. This is fairly similar to Sloth's post for a Z4M-mirror glass replacement http://www.z4-forum.com/forum/viewtopic ... 30#p750478, but it's a bit different for a few points so bear with me...

Background - on the day of the MOT, I get into the car to find this:



You can see the fluid used to dim the mirror has 'leaked' out of the glass sandwich it's usually trapped in. I was lucky - it's leaked out of the casing and the only additional damage it has done is 'melt' the alarm indicator lens where it's run down the outside. There have been horror stories of the stuff dripping out onto the gearshift/centre console and doing all sorts of surface damage there.

Apparently this happens often when the car is left in sunlight (what, a convertible, in the sun?!) and the seal around the glass sandwich fails - leaking all the alien blood out.

So what now? As you can see in the pic, I've removed the cover from where the mirror arm attaches to the screen - it's in 2 halves and separates easily - just gently pull them apart. Then remove the mirror - it is attached to the windscreen at the top of the arm, it locates onto a metal stud bonded/integrated into the glass. Rotate the arm 'clockwise' about that top pivot point (move the whole assembly to the left and then up) and the whole thing will be released from the screen. There will be a cable that you need to unclip to totally separate the mirror from the car - be gentle and unclip the cable.


Next step: buy a mirror from ebay. I bought one for a 1 series after having no joy finding one for an E85. I would have bought the glass only from http://www.mirrorjohn.com/ but I have a lowly 3.0 and not an M, so I don't have the M mirror... at this point I should credit MirrorJohn as his website was great for helping me formulate a plan. If I had an M, I'd have bought my glass from him.

'New' on the left, 'old' on the right


Ok - so I did try the new mirror in the car to see if it'd be ok - I mean, it looks almost identical, right? Nope - there is a radio receiver in the Z4 mirror that is used for the central locking/alarm, which meant I had to transplant the glass or the receiver. I chose to swap the glass and the alarm indicator lens.

Using a flat-bladed screwdriver, I gently prised the bezel off - easy to do without breaking anything if you are patient. A photo so you can see the locating lug points.


And the back of the glass looks like this. The glass is made by Magna Donnelly, which apparently are the makers of the ones that often fail in the E46 M3 - apparently BMW changed to use another manufacturer in 2007.


Detach the cable and the glass is free of the housing. Notice the sticker on the back of the housing - it says the radio receiver (the board at the bottom) operates at 433 MHz.


I did the same to the 'new' mirror, same method. The plastic housing has the same part numbers/moulding markings. Looking at the inside, the board at the bottom is different and there is no sticker on the back.



The back of the 'new' mirror glass is also very different. Looks like it's a different manufacturer and it has a completely different control board. The mirror glass appears to have been made in 2009.



The pins to connect the glass to the mirror housing look identical, the cables in the mirror housing are the same colours and sequence. I decided to chance it. I popped the 'new' glass into the 'old' housing, put it all back together and tried it in the car. It works!

It's a fair bit cheaper than buying a brand new mirror from a dealer, the 1 series mirrors seem to be a bit more common on ebay so to get one to sacrifice the glass should be just as easy.

Hope this helps!

Good info and an excellent write up

Nice write-up, thanks

Got to give back to the forum somehow!

I've learned a lot of useful info from here and while I don't post that often, I do lurk from time to time!

+1 on the great write up.

Thanks!

One thing I did forget to mention - if you do buy a mirror from ebay, make sure it is an auto-dimming one - the standard mirrors can also use the same housing and will look largely the same. A key way to tell is to look at the top of the bezel for a small 'window' which holds one of the light sensors - the other sensor is on the 'back' of the mirror that faces the windscreen. If you can get one for an E85, you can just swap the unit over - if you get a 1-series mirror, you'll probably have to do the glass transplant as above. Not sure if the E86 has the radio receiver in the mirror or not, I can't remember what RealOEM says about it - it's worth checking first.

If any one of you is interested in this auto-dimming mirrors, here's a good read on when and why it happens. And what damage can cause.
http://forums.m3cutters.co.uk/showthread.php?t=82329

Thanks to the OP for this post , yet again the forum comes to the help of fellow members. I had to do this after I left my car in the blazing heat of Tuesday and Wednesday , and came back to the dreaded bubble in the middle of my mirror , lucky for me the alien gel between the glass layers hadn't escaped and damaged the interior. If you haven't checked your recently after the hot spell......go and check now !

I too got a 1 series mirror instead of an E85 just like the OP and the hole job took about 20 mins .

Great Post thank you.

I have the exact scenario as described above on my E85 Z4M Roadster, right down to the stain/corrosion on the clown nose. Left it parked in 30+ DegC sun and came back 8 hours later to find a pool of strange dark fluid around the gear lever. Fortunately the fluid was caught by the leather boot around the gear lever and I managed to wipe it up before any obvious damage was done. I have experienced some General Module issues for a few days after (some have called this the possessed car issue - random misoperation of top, windows, radio, dash lamps), but these seem to have been sorted out by charging the battery after disconnecting it for 30+ minutes which I read somewhere resets the modules. - (EDIT) Ok I have now found a drip of the dimming fluid on the 315MHz Radio/LED card, that might explain battery dropping to 10.7v overnight when car was locked. It seems that the battery low voltage "brown out" plays havoc on the modules as it causes a partial loss of the various functions. I expect that a card fault, caused by the drips of fluid, was discharging the battery so the card will be cleaned using electronics cleaner fluid and see how we go with that problem. Fortunately there is no sign of corrosion or other damage on the radio/LED card. In the mean time the remote locking and remote top up/down functions, which are the purpose of the E85 315MHz radio card, do not work.

after 3 days the battery voltage has been holding up, so worked on the following temporary fix to get me driving again.

1) Removed and cleaned the 315MHz radio card with aerosol isopropyl alcohol bought from an electronics shop.
2) split the mirror glass and cleaned out the last of the offending liquid as per https://www.youtube.com/watch?v=ZANJOlEqJZ4.
noting that I found the sealing
3) totally removed the dimming electronics module from the mirror and safely stored it in an electrostatic bag for later.
3) used double sided sticky tape to stick the mirror glass panels together.
4) reassembled the mirror, 315MHz radio card and installed back in car.
5) tested all functions working (except auto dimming).
6) pat myself on back for $12.95 TEMPORARY fix - $3 tape + $9.95 cleaner fluid.

I have found that my longer term options for the mirror are:

a) Buy new OEM replacement mirror at $750AUD

b) Mail mirror to USA (radar-mirror.com at $140AUD) or Holland (sybesmas.com at $250AUD) for re-manufacture
and put up with stained clown nose.
Noting that mirrorjohn.com and burkhart-engineering.com only offer the "oval" M3 style mirror/glass replacement
and nobody does this here in Aussie.

c) Buy used E85 mirror and risk getting another Magna Donnelly one with its know leakage issue and risk interior trim damage etc.

d) Do as above at $70AUD incl post from UK - again no mirrors available on ebay in Aussie.

Since I have had the original mirror (EDIT - BMW #51164363965 with the Donnelly Electronics Type E85 EC + LED + 315MHz Radio) out of the car and opened it up I understand what is involved and it looks really straight forward, but before I commit I would like to know which BMW part numbers or E8x models to look for (EDIT - I think BMW #5116 9134394 is the best option as earlier 1 Series may have also had the Donnelly Electronics EC Unit & from mirrorjohn.com BMW changed from Donnelly to Gentex in 2007). For those who have applied this fix please let me know your experience.

Many Thanks In Advance

Great write up thanks

Awesome write up Dev

- E87/E81 mirror off the bay - £10 (make sure you get one with the little window in the top of the mirror surround/bezel)
- 20 minutes of my time stripping out the glass and swapping it with my surround - taking care with the bezel cips
- A plastic trim splitter was the only tool needed (i used one from a mobile phone battery kit - bit flimsy but did the job)

Back in the car and fully working

Only wish id done it 18mths ago when it first turned to a blue pool on a very hot day (fortunately no drips)

You're welcome, glad it's still coming in useful!

Big thanks to Dev for this info, just renewed my failed auto dimming mirror with an e87 unit.
Once split it was actually easier to leave my mirror housing on the screen and swap the glass over sat in the passenger seat

Thanks for the info!! What’s the part number for the entire rear view auto dimming mirror for an M e85? Or should I get just the mirror? The fluid is also my issue.. thanks

Where are you and how long can you wait? I have a good one at home but not back until 2nd Jan.
Assuming all versions use the same mirror of course