DIY Keyless Entry on a W126 - Page 2 - PeachParts Mercedes-Benz Forum

thayer · #16 02-17-2010, 06:36 AM

that trunk lock works on vacuum with the rest of the system. The key should have been able to unlock the trunk even with the vacuum system in "lock" mode.

Phil · #17 03-15-2010, 01:57 PM

Has anyone connected their keyless system so it flashes the parking/corner lights when you lock and unlock the car? Did you add relays to do this or how did you set it up?

ah-kay · #18 03-15-2010, 02:47 PM

I did this with my 300D. I soldered the control lines from the Keyless unit to the fuses connector ( there are 2 fuses in the fuse box which control the parking lights ) as there are relays in the Keyless unit. Either end on the fuse terminal is OK. If you can locate the wires to the parking lights then splicing into them would be just the same.

On the 300SDLs, I located the control unit in the trunk lock void and I never bother with the parking lights. I would imagine I can splice into the parking light wires inside the lens and it should work. Too much hassle.

thayer · #19 03-15-2010, 02:54 PM

Fantastic. I'll try to run it to the fuse box. I was very hesitant to start splicing wires anywhere else.

Phil · #20 03-15-2010, 04:35 PM

I'm looking at the wiring diagram for the car and the light switch switches the + side but the keyless unit switches ground so how or where would I connect the - to switch the lights?

ah-kay · #21 03-15-2010, 04:42 PM

Quote:

Originally Posted by Phil

I'm looking at the wiring diagram for the car and the light switch switches the + side but the keyless unit switches ground so how or where would I connect the - to switch the lights?

Are you sure the Keyless unit switches the -ve?

It is a bit unusual unless the Keyless does not come with an internal relay. If that is the case then put 2 relays in there to reverse the logic to switch the +ve. It should be very straight forwards. May be just 1 relay if you switch them together.

Phil · #22 03-15-2010, 05:01 PM

Quote:

Originally Posted by ah-kay

Are you sure the Keyless unit switches the -ve?

It is a bit unusual unless the Keyless does not come with an internal relay. If that is the case then put 2 relays in there to reverse the logic to switch the +ve. It should be very straight forwards. May be just 1 relay if you switch them together.

It definitely switches the -and it does have internal relays. It looks like I could add 1 relay to switch a + signal but feed it through 2 diodes, one to each side so I don't cross signals to the parking lights but I'm open to any suggestions.

DieselPaul · #23 03-15-2010, 09:05 PM

With 1 actuator on the drivers door, will it unlock all 4 doors? My car is a w124, but I'd imagine it is similar.

ah-kay · #24 03-15-2010, 10:00 PM

Quote:

Originally Posted by DieselPaul

With 1 actuator on the drivers door, will it unlock all 4 doors? My car is a w124, but I'd imagine it is similar.

What do you mean by actuator? You suspect the driver door lock is not vacuum controlled?

I am not familar with the W124. If you can lock/unlock the whole car with the trunk or passenger door then you do NOT need an actuator at the driver's door.

mplafleur · #25 03-15-2010, 10:37 PM

Yes, with the central locking system, if you actuate the driver door to the lock or unlock position, all the other locks will follow suit.

Phil · #26 03-16-2010, 01:34 PM

Quote:

Originally Posted by DieselPaul

With 1 actuator on the drivers door, will it unlock all 4 doors? My car is a w124, but I'd imagine it is similar.

You would only need to have an actuator on one of the locks that activates the entire system. I wonder how hard it would be on your car to put it on the trunk lock?

ah-kay · #27 03-16-2010, 01:39 PM

You need to make sure you need an actuator FIRST. If you can unlock/lock from the trunk or passenger door then you do NOT need actuator. W126 300SDL definitely do not need one. I have put Keyless system in all 3. Not sure about w124 but I doubt it needs one. I need actuator for the 300D and 190D.

Phil · #28 03-17-2010, 01:36 PM

Quote:

Originally Posted by Phil

It definitely switches the -and it does have internal relays. It looks like I could add 1 relay to switch a + signal but feed it through 2 diodes, one to each side so I don't cross signals to the parking lights but I'm open to any suggestions.

Anyone have an opinion about what will be better, two relays or one relay and two diodes? I'm thinking of the diode method just because it seems more interesting but looking for suggestions.

brownmal · #29 06-08-2010, 11:57 AM

If you choose to buy a new keyless entry, don't use USKeyless. They are HORRIBLE! I ordered from them as well. They didn't even ship the part for over a month after purchase despite numerous calls/emails. They were eager to respond until they got paid, then NOTHING. They won't answer phone or return e-mails. Their installation instructions are the worst I have ever seen. It says something like "Chooser the brown wire" when there is over 100 brown wires. They are NEVER available for assistance even though they claim assistance available (and website says avail even on the weekends for assistance). Now it has been 3 months, my car still has the floorboard tore up awaiting a PROMISED e-mail with pictures, but nothing. I have asked for a refund, but they won't respond. STAY AWAY from USKeyless!