I have a 1987 Benz 300td Wagon

the seat belt light Flashes constantly when the car is on and the Courtesy or door lights only on the front stay on even if the car is off I have no Clue what to do or what it is Can anyone PLEASE help me
the doom light turns off as it should .... i dont know what to do

This sounds like a bad door switch.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Hello and welcome fellow 300TD owner!

A question-
- when you have the control switch on the dome light pushed all the way forward (door controlled position) does the dome light turn off automatically after a few seconds?
(The symbols are confusing, half moon is door control, half moon with sun rays is on all the time, O is off, book is reading light)
Note these are the same symbols on your center console for the rear compartment lights.
Or are you turning the dome light off with the switch by moving it to the O position?

If you have to turn the dome light off manually, let's do like vstech says and check your door switches.

If the dome light is in the door position and it turns off by itself after time delay, that would be really odd if your seatbelt and puddle lights stayed on. They are all switched from the same point.

You actually have 2 door switches on each side, the lower one is for the power seat relay, that lets you adjust the seat with the car off and the door open. You can confirm this by exercising the switch and listening for a click in the fuse box, that is the relay for the power seat controls operating.

The upper switch is the light control. It can be removed by pinching the sides and pulling it out. I would remove the light switches on both sides and test them for continuity. You should have continuity when the switch is extended and none when it is pushed in.

While you are in there, make sure the wires are not touching the frame. The switch operates on the ground side of the lights, so it will not blow a fuse, but that will keep the lights on if there is a short.

Switch part number 001-545-87-14 if that's the problem.

If not you will have to get a copy of the wiring diagram and trace it out. Something is bringing the control wire to ground.

Here are a couple invaluable resources
w124performance.com
w124-zone.com - link to factory manual, with a better copy of the wiring diagram than the MB site
startekinfo.com, select MB workshop resources, scroll in about 3 pages to Model 124 Service Library - another copy of the factory manual
epc.startekinfo.com - the same system the parts guy at the dealer uses, it will ask you for a credit card to prove you are in the US, but will not charge you
and of course pelicanparts.com

Finally edit your profile, so we know where you are located!

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

i will try this TODAY guys Thanks so much i will be informing you as to if this works http://www.flickr.com/photos/65834580@N07/11617454406/in/set-72157639139431454/
this is my Car id hate to know i shorted out the wires some where .... !!!!

I can't add much to jay bob's thorough analysis except to confirm that the problem should be found in either left or right front door lamp switches or in the N2/4 Warning Module. This latter thing is located behind the instrument cluster and is the thing that buzzes to remind you to buckle your seat belt, keys left in ignition, headlights on, etc.

In my '87 sedan, the door switches had been reversed upper-lower on one side. You can experiment to see which is which: with either front door open (ignition off, keys in your pocket), use the seat control switches in the door to move the seat, then push the two door switches one at a time until you find the one that stops the seat motion. The other one is the lamp switch, which may be bad.

If you do find that one of the switches is bad and can't immediately find a replacement, you can rob the switch from one of the rear doors. Put tape on its wire terminals so the rear lights won't stay on all the time.

If all the switches test good, the warning module could have a fault, although its typical failure mode is to fail "off" rather than "on." Let's hope it's a switch, much easier to fix.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

Thanks guys Turns out my door Switch's !!! just a day or so later and the seat stopped adjusting so fixed and Ready now !