DIY Auto Dimming, Homelink, and Compass Rear View Mirror upgrade W124

[arcticathlon]

I just wanted to share with you my weekend project of installing a new Auto Dimming Rear View mirror with compass and Homelink (3 garage door openers), that I performed on my 1995 W124 E300d. I purchased this mirror from 2phast Motorsports at mirrors.2phast.com . cost was $150 plus $15 shipping, which i thought was reasonable. He sells mirror kits for W201, W126, W123, R107 cars as well.

Reason for upgrade was that my current rear view mirror had self destructed. You will be able to see exactly what happened, as some Nutjob "Service Specialist" at a dealer probably thought it was a good idea to grease the plastic ball-and-socket joint of the mirror. I am assuming that the previous owner (doctor's wife) complained that the mirror was a little hard to adjust, so someone helped her with that request. Well, the end result is that the grease slowly leaked inside the mirror and softened the plastic. I only drive my car 10 miles to work everyday, and never drive at night. When i finally took it out at night one day, and flipped the dimmer, it exploded. (see picture 1 below)



So, I needed a new one and thought that i might as well upgrade to an auto dimming. The Homelink feature is very neat and I hate to have the ugly garage door opener spring deform my sun visor, so the upgrade was a no-brainer.

Procedure:

Step 1: Remove mirror by grabbing it and bending it away from the windshield. It is held in place by a spring mechanism that is just a pressure fit. Once that is popped out, remove the three screws that hold the metal mounting bracket in place. (See picture 2 below)



Step 2: Next you must pop out your dome light switch. Insert a flat blade screw driver on the Passenger side (right side in the picture below) of the dome light, as that is where the pressure springs are holding it in. The driver side has the plastic hinges, and if you try to remove it from that side, you will only break your headliner or the dome light assembly. Once it is remove, it will look like it in Picture 3.



Step 3: Disconnect the 6 Pin power connector. The 6 pin connector is on the Left side, and the right side is only a 5 pin. Once removed you can verify that it will look like this. (see picture 4 below)



Step 4: Next we need to find the pin that is our ground and our Switched power. Take your keys and turn them to the position before you engine starts. This will only provide power to your mirrors when you have your keys in the car, and will NOT drain your car slowly. We will not want to connect to a constant 12v with this installation. Pin 4 is our Switched 12V and pin 6 our ground. Below i show it providing power only after having inserted the key, before that it read 0v.



Step 5: Pop off the back cover of the 6 pin connector to located the correct cable going to Pin4. In my case the cable was a black cable with a yellow line on it. Pin 6 is the Brown cable (ground is always brown).



Step 6: Connect a wire to the pin 4 and pin 6 to give power to the mirror. This can be cone many ways. There are many types of clip connectors that allow you to connect to the wire easily, you can solder more cables to the same pins in the connector, etc. This kit came with these quick connectors that you just snap on the cables, which i ended up using. Normally i would solder another cable on the connector, but this time i was short on time and took the shortcut. Pull the protective tape away from the connector to expose more of the cables, so that you can connect the vampiric connector. You can connect to both cables on the connector, but i ended up connecting the ground clip to the cables that were grounding to the chassis. See picture below where both clips were attached.



Step 7: Connect your kit supplied power connector and route it under your headliner to pop out of your hole where the old mirror came off. This is easy and is not going to damage anything. It took me 20 seconds to do, so no show stopper. once you have it routed, re-install your metal mounting plate, and connect your mirror. You will notice a metal car stereo removal key that is inserted in the spring of the mirror base. This came with the kit and is a great idea. These springs are very strong and very difficult to install. this key allows it to already be compressed and makes it much easier to install. Once it is mounted, you just pull the key out and it is in there for good. Before you fully install it you must Test it first.



Step 8: If the mirror turned on as expected then you can install it. Congratulations you are done. Sit back and have a Dr. Pepper (Texas country) or your beer of choice.

[Walkenvol]

Nice job!

[gatorblue92]

Nice! I have been debating adding one of these to my 240D for a while now.

[Zulfiqar]

same thing happened to my mirror about 4 months ago, flipped the dimmer and CRAAAAACK

[Jeremy5848]

Interesting failure mode and nice DIY write-up. Have you tried the auto-dimming feature yet? I assume the instructions include programming the Homelink?

Jeremy

[arcticathlon]

Yes, the instructions are emailed to you when you purchase the kit, and were descriptive enough, just basic in the pictures showing wiring. I wanted to put this DIY out there, to clear up the steps for anyone with a W124.

Auto Dimming works great, and is pretty nifty.

Homelink instructions are the same for any type of car with homelink. Press and hold the outside buttons for 20 seconds to erase all codes, and then hold the button down with the remote close by. newer garage door openers you have to press the "Learn" button on the back of the housing.