Buzzer

[bpossel]

Continuing to bring my 280sl back to the original condition....

 :?: Yesterday I removed the mass of wiring that was associated with an older alarm system installed by the previous owner.

Found a small item under the dash, drivers side unplugged.  Plugged it in.  Now when I open my door (no key in ignition), a buzzer sounds.

Question: Is this normal that the buzzer sounds when the door is open, no key in ignition?
Thanks!
Bob

bpossel
Memphis, TN.
1971 280SL
1997 E320

[Douglas]

Something isn't right -- the buzzer is meant to tell you that your door is open and the key is in the ignition.

Douglas Kim
New York, NY
280 SL #016220

[bpossel]

Hi Doug,

You were right!  Even though I tested starting the car at each step in the removal of the old alarm system and also plugging in the old buzzer, this morning when I tried to star the car, it didnt turn over at all.  What is odd is that the clock, and head lights worked fine.  I thought that maybe the battery was dead, but with the lights working, battery was fine.  I unplugged the buzzer and turned the key again.  Same thing, nothing.  I also noticed that I didnt hear the fuel pump prior to starting the car.  Anyway, said a prayer, and tried one more time.  It started!

Not sure if it was the prayer, or disconnecting the buzzer?  Anyway, drove the car several times today, starting it and stopping it while shopping and all was working great!

Any other ideas on how I can find the short?

Thanks!  Hope all had a great holiday (US Labor Day)

Bob

quote:Originally posted by Douglas

Something isn't right -- the buzzer is meant to tell you that your door is open and the key is in the ignition.

Douglas Kim
New York, NY
280 SL #016220

bpossel
Memphis, TN.
1971 280SL
1997 E320

[jeffc280sl]

Hi Bob,

The warning buzzer, buzzer switch on steering column, door contacts, entrance light, clock, trunk light and center cluster light are all fed from fuse #1.  Continuous power is available at this fuse.  You do not need to have the ignition key in any position for these circuits to work.  Do all of these devices work correctly?  What color are the wires in the buzzer connector?

The fuel pump is fed from fuse #4 and the key must be in the on position to get power to the pump.  When the key is in the on position you should hear the fuel pump running.

It sounds to me like you have two unrelated problems. Disconnecting the buzzer does not cause the car to start on the first try but it does on the second.  Can't be.  I think the ignition starter switch is intermittant.  The fuel pump and starter did not work and worked at the same time.  You did not have the fuel pump working and the starter fail.  Same goes for the fuel pump not working and starter working.  To me it all points back to the ignition starter switch.  Both the starter and fuel pump are fed from this switch.  

I'm not sure how to check or fix this.  I'll give it some more thought.  Maybe someone else can help.

Jeff C.
1970 280SL 4-speed