Can one put keyless entry in an 87 126?

[John Winn]

Hello group,
Since I can't find anyone who knows why my alarm is wacky since I changed the radio I have concidered installing a new alarm with keyless entry..I read the article on the board how to do it in a 124, but are there similar directions on a 126? I see the 87 locking system is electrically controlled by switches in the vacuum device in both doors and the trunk that control the pump but I can't decipher the wiring diagram well enough to know what I need to hook up..I have had really good luck with code alarm..But this time I think I am gonna do it myself..The local "mothers window tint" is trying to sell me a top of the line "remote start" model..I told him it is a diesel (300SDL) and he is telling me it will work..I tried to explain to him it won't because the engine shut off is vacuum controlled...Figure I don't want these guys working on my car! Anway if anyone knows how or a link to do this I would greatly appriciate it..Thanks a million! John

[bstreep]

John,
I wrote the directions for the 124. I have corresponded with Tom Pindelski, who put one in his 560SEL (a 126, I believe). He had some wiring trouble and got help from Omega, the alarm maker. He sent me the PDF for wiring, and I can email it to you, just give me an email address (bstreep@satx.rr.com). Also, if you are going to Mothers, it sounds like you are in SA or Austin. If you would like some help, I'm on the north side of SA, and I'd be glad to help. Tom also managed to wire his lights and a horn to his for audio and visual, if anyone is interested in how he did that, just email me.

Good Luck,

Hi John,
Getting away from the window tint guys was a good move. I'd bet they would get 90% finished butchering the wiring before it occurred to them that a remote start wouldn't work on a diesel without some serious modification. Over my own objections, I put a remote start system on a 560SEL 7 years ago. I spent about a day and a half to get it installed properly... no "Scotch Locks" or cut wires, soldered connections at terminals, routed the wires along existing harnesses, etc...I thought I'd done a fine job of turning "chicken excrement" into "chicken salad". The customer had an absolute "cow" over the bill! The moral of the story? To do it right usually exceeds the cost(or perceived benefit) of the aftermarket system.
I would stick with the factory alarm. It's easy enough for anyone familiar with it to diagnose and repair. Besides,if somebody really wants to get in your car...they will.
Regards,
Randy D.

[96C220]

When u swapped out the radio, did u ground the pigtail wire that went to the back of the radio with a clip? It clipped directly to the back of the radio chassis, not to any electrical connector. This is the wire that is designed to activate the factory alarm in case the radio is stolen. Back in the 80's radio theft was a huge problem, and it seems that MB went to all sorts of extravagant measures to protect the radio. Make sure that wire is properly grounded, all the ones I have seen have been black with what looks like a spade connector on the end of it, otherwise it will cause all sorts of intermittent problems with the alarm.

Best wishes and take care,
George Androulakis

[Thomaspin]

Wiring, pictures, you name it, everything you need is on my web site - you should follow the late W126 version. I disabled my alarm in the 560SEL (two plugs in the passenger footwell) as I like the 'lock on start' feature but that sets the factory alarm off.

The early W126 has a different circuit, so make sure you look at the right pictorial. Your installation will be in the trunk where the vacuum/pump for locking/unlocking resides. It's in the right rear corner of the wheel well, where the spare is.

I go the whole hog here with horn honks and flashing lights - you don't have to do those, but they are nice to have.

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