Mercedes-Benz Forum banner

DIY Smoke and Mirrors Revisited!

62K views 62 replies 37 participants last post by  2.7 TT  
#1 ·
Hi,

After owning my sisters S500 for a few months, I noticed my passenger mirror to always go up when using the memory buttons. A few months later, more symptoms appeared which were an occasional blown #30, 20A fuse when tilting the steering wheel. I installed a 25A fuse and was well for a few more months. OK, let's try a 30A fuse then the smoke show occurred while moving the mirrors out of tucked position. Well, after reading about other owners experiences, I decided to tackle a repair vs. buying a new mirror(s) for $$$.

I was lucky that no permanent damage occurred and snapped a few photos to share with all. I searched many mirror topics and couldn't find how to remove the outer housing. My 97 S500 appears to have a one piece housing compared to the ones I've seen with exploded views displaying 3 pieces. It is also not neccessary to remove anything from the passenger compartment.

Basically, tuck your mirrors all the way, unscrew 3 screws, unbolt 2 electrical harnesses, unlock the outer mirror housing, and the inner mirror assembly pops out.

Good luck!



















 
#3 ·
Awesome write-up! :thumbsup:

Please re-post this in the "knowldge base" thread too.
 
#5 ·
THX! If you had a wiring diagram, it would be rebuildable. I almost replaced the wires by cutting and splicing in w/solder joints. I may do so in the future if the rest of the rubber loomed wiring goes south. They appeared to be unscathed by heat, moisture, and bending when moving mirrors.

OUCH on the two new mirrors...:eek:
 
#10 ·
Same problem happened on my friend's 97' S320 (W140)
the problem is...... If you want to remove the screw behind the side mirror, you must fold the mirror first, but everytime press the button to fold it, the fuse will burn, may I know is there any other way to fold the mirror to let me remove the screw? thanks a lot.
 
#11 ·
the wiring harness all over the car was made out of low heat rating, they tried cutting corners during engineering and production, mostly the wiring harness on the engine side tends to disintegrate, very few cases of side view mirror suffering from that defect although it is common.
 
#16 ·
Thank you very much for your guidance.

I have aquired 7 colors of 3/32" shrink tubing. My question is whether to use it to cover all portions of the wire including those portions with intact insulation, or to try and strip the insulation from the wires so that everything becomes bare wire?

Looking at your photos it appears that you have replaced some of the wire with new wire. Are my obsevations correct?

Thanks again.
 
#18 ·
Hi there,

My wiring was so bad that i decided to attempt a rewire having resigned myself to the fact that I was going to have to spend ÂŁ400 GPB on a new one anyway, it was "do or die"....

Be very careful - if like mine, you have no way of discerning what colour enters the plug - when you open the connectors the pins jump out and you have no way of knowing what went where.
STOP
Before you open the plug, under a magnifying glass and bright light (I used a soldering station with arms and a large maglite), very close to the point of entry to the plug, the colours are just discernible allowing you to map colour to conn number.

The pins inside the plug can be opened very carefully and new wires inserted and reclosed. For good measure upon completion I wrapped the new cables into a loom with self-amalgamating tape which is much more weather resistant than insulating tape.

Mine now works perfectly.

When I do the second one, I'll photograph the stages and publish a wiring diagram of the appropriate connections.

Hope this helps :thumbsup:Newbie

--- S600L --- V12 --- 1996 ---
 
#19 ·
Thanks for the information. I was able to apply shrink tubing, and by pulling the wires one at a time and covering just that wire, I was able to get the mirror operational again.

There is a continuing problem in as much as the memory capability has vanished. Every time there is a driver change, the mirror in question has to be independently adjusted. I have no idea what the problem is.

Any suggestions would be appreciated.

Thanks
 
#20 ·
Now THAT's good material! Nice format, well done.

The wiring material on the later 140's (98-99) seems a little more robust than the earlier runs. When I rebuilt my mirrors a few years back, only one or two wires had chaffed. The rest were in remarkably good shape.

I replaced the entire wire-runs with marine wire, and found a marine plug set as well. As I recall, the retract/extend mechanics drove me crazy.

All the best -
 
#21 ·
I took the easy way out and only covered the wires in the mirror, and did not go into the door. I hope that this solution will last me.

On the issue of memory, I understand why mine vanishes, what I don't understand is why the mirror's memory has vanished, leaving all other seat and opposite mirror memory functions intact.

Where should I look?

Thanks
 
#22 ·
I think you may still have an issue with your mirror in question. You may have to go over it one more time and look for a short or disconnect.

Good luck!
Mo
 
#23 · (Edited)
Before and after

Using this DIY as guidance, here's my before and after. This is the pax mirror on a 98 S500. Driver's side was done a while ago.

Like yours, my pax side was also on fire! The kids snapped a photo with the iPhone but it didn't turn out. It blew the usual fuses (position 30) but it didn't burn up the relays. Same fuse deactivates all of the seat and mirror controls.

The part# on this harness is 124 508 00 52(?) but even the dealer did not find a match. Do one of you guys that works in an electronics shop want to make up a few of these harnesses for forum users (Heck, I'd pay $25 for it)? Supposedly they fit numerous models 93-99.

Finally, I used marine wire and marine dual-layer shrink tube. Supposedly the inner layer melts at a lower temp and makes the whole thing water tight. Do an Internet search for a source, plenty around.

Dealer cost: Mirror + installation: $1,289.00
My cost (with the help of this EXCELLENT DIY): $21.00 for marine grade wire

Before:


And After:


geebee
 
#28 ·
Once again, this thread is resurrected. Great write up. This looks like the fix I need.

An additional symptom my S500 has is that the steering wheel adjuster knob does not work the steering wheel, but instead causes the passenger side view mirror to move out. If the wiring in my side view mirrors is bad could that somehow cause the steering wheel adjuster issue???
 
#29 ·
There is a high chance. Open one of your side mirrors and double check yourself.

-You need to pull the triangle from the inside where the mirror is bolted.
You need to pull the top corner of the triangle first then the sides. If you pull the sides you're most likely going to break the clips.
- Once the triangle is out you will see 3 nuts, if I recall they are 10mm.
- Once the nuts are out the mirror can unplugged and removed from the outside.
- Check the wires if they are corroded.
It shouldn't take you more than 10 minutes.

Also not all mirrors are like the one picture on here. Mine for example were totally different and couldn't be opened all the way to the motor. Thankfully though, the reason why my mirrors didn't open or fold all the way was because it needed to be lubricated. Your case sounds like a shortage in the wiring.
 
#30 · (Edited)
Great Write Up Same Problem Here. Question

How does one use a screwdriver to remove each wire one at a time from the connector so a shrink tube can be slid over the existing wire? Well, I figured out that the grey part of the connector slides sideways, and a small screwdriver will push down the pins so they can be removed.

Also, how did you pull the connector (and harness) back through the small hole in the frame as shown going from the 9th picture to the 10th picture?

I figured this out too. I did not realize that the mirror had to come off the frame in order to loosen three motor screws in order to pull the wire harness back through the slot.

Now that I figured all that out, I put the shrink tube on, put everything back together and it works great. Thanks for the pictures and instructional write up!