Whenever the glow plug relay cycles on this car ~ 1985 European 300TD .

The horn I hear beeping , is a weak little thing , maybe under the dashboard ? .

If I just ignore the beeping & flashing , it stops after a minute and the car will instantly start , every time .

I was wondering if maybe it had a factory alarm that's going bad ? .

Any ideas would be greatly appreciated .

TIA ,

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

That's the standard "door is open with the key in the switch, or the lights are on" Mercedes buzzer. They make unusual sounds as they wear out but that's undoubtedly what it is. So, it's supposed to do that. It buzzes constantly when 1) the door is open with the key in the switch, 2) the door is open and the lights are on, and 3) while the fasten seat belts light is on.

The timing of the buzzer with the glow plug light is just coincidental. it's actually the seat belt light that you should notice a direct parallel between its flash and the buzzer's duration. 5-8 seconds I think.

__________________


~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

The only horn the factory alarm uses is the car's main horn and possibly an extra one buried somewhere in the engine bay (I think I've heard that some have this) so that the thief who cuts the wires on the main horn still won't get away with it. But that's definitely all in the engine bay or the car's exterior rather than the dashboard.

__________________


~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

THANX ! I can start all the other Mercedes I've seen with the door open and never had this .

The key buzzer is supposed to be intermittant ? .

I think about 5 second bursts is right , wher do I begin to look ? .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Not sure what you mean, but I've never seen a Mercedes this age with an intermittant buzzer of any kind.

If you open the car door and turn the lights on, you should get a steady never-ending drone from the buzzer.

If you open the car door, put the key in the switch, turn it to "on" and then turn it back "off" but *don't pull it out of the switch* then you should have a steady, constant never-ending drone.

If you get in the car, close the door, leave the lights off, and turn the key on, you will hear a buzz until the seat belt light goes out and then it will stop buzzing at the same time that the seat belt light quits.

~~~~This may not apply to you~~~~
My 1986 never ever turns the buzzer on if you get in, close the door, buckle your seat belt, and THEN turn the key on. It detects instantly that none of the conditions (Door open, belt off, lights on) are being met, and so it doesn't buzz at all. I do not know if this is true on an 85 or not.
~~~~
Look for what?

__________________


~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

Whenever I try to start this car , the glow plug lamp flashes on and off , on then off , at the same time , I hear a beep , beep , beep.......

When the lamp goes out and stays out , the beeping stops (it only makes the beeping noise when the lamp is on for a few seconds) and I turn the key to the start position and it cranks and lights right off .

So , what the heck is this thing doing and how to make it stop ? .

I've never had one with this noise before , not for key , not for seatbelts , nothing .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Oh. I apologize. This is... completely unrelated to what I thought it was.

It's definitely not supposed to do that. The glow lamp should never flash on and off like that regardless. It's almost like... a relay such as a turn signal relay... has gotten cross-wired or cross-grounded or something, into the glow system. Wiring fault or something. At this point somebody else is going to have to help out more because I have NO idea.

I thought you were just confused by the door buzzer acting suspicious but that clearly isn't the case anymore, so sorry for the confusion.

__________________


~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

Youy tired to help and that's what I wanted .

I've been a VW mechanic since long before they had key/door buzzers and this sounds more like a weak ir tiny little horn beeping....

Beep

Beep

Beep

Beep

Beep

Like that .

it's really wierd and I can live with it (I think) but I'm building this car for SWMBO as she asked for it (and , truth be told , I use all my vehicles kile pickup trucks and this one is too nice for me to ruin loading it full up with old engines & parts...) and she allready gets nervous about the way the oil pressure gauge wiggles @ hot idle with the AC on so I know she'll not be able to relax and enjoy this car with this wierd little fault .


Others are viewing this and will soon hopefully chime in .

Maybe I'll get lucky and it's just a corroded aluminum fuse that'll behave once I replace them all as I always do ~ so far , no touching other than initial cleaning & polishing .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better