I HAVE A RELATIVELY MINOR PROBLEM THAT IS ABOUT TO DRIVE ME CRAZY!!
I HAVE A 1986 420 SEL- MY PROBLEM IS THIS:
MY POWER SEATS ONLY FUNCTION WHEN ONE OF THE FRONT DOORS IS OPEN, REGARDLESS OF WHAT POSITION THE IGNITION SWITCH IS IN.

CLOSE THE DOOR, NO PWR SEATS, EVEN WITH THE IGNITION SWITCH ON.

I TRIED A QUICK FIX BY JUMPING THE 2 WIRES ON THE DOOR SWITCH, SO THE SWITCH WOULD BE "FOOLED" INTO THINKING THE DOOR WAS OPEN...TURNS OUT I WAS THE FOOL AFTER DISCOVERING A DEAD BATTERY AFTER A WEEK WITHOUT DRIVING.

THERE IS NO MENTION IN THE CHASSIS MANUAL AND VERY LITTLE TO GO ON IN THE ELECTRICAL TROUBLESHOOTING MANUAL. I CANNOT SEEM TO TRACK THE PROBLEM DOWN. I HAVE PULLED THE INSTRUMENT CLUSTER, UNPLUGGED THE HARNESS FROM THE IGNITION SWITCH, FOLLOWED THE WIRES UNITL I COULD NOT ANYMORE, AND NO PROBLEMS WERE FOUND. (AT LEAST EVERYTHING LOOKED OK)

I EVEN REPLACED THE WARNING BUZZER SWITCH ON THE STEERING LOCK(I KNOW IT CONNECTS TO CENTRAL LOCKING, AS WELL AS THE WARNING BUZZER) NO LUCK, BUT NEEDED REPLACED ANYWAY.

BTW, THE ONLY TIME THE WARNING BUZZER SOUNDS IS WHEN I LEAVE THE HEADLIGHTS ON.

I KNOW THIS SEEMS SMALL, BUT IT WOULD BE NICE TO BE ABLE TO ADJUST MY SEATS WHILE GOING DOWN THE ROAD.

ANY HELP WOULD BE APPRECIATED.

THANKS

__________________
2000 ML430 86k
2000 C280 Sportline 100k
'86 420 SEL 178k
'91 Audi 100 179k
'88 BMW 750il 167k
'83 300 SD 167k (sold)
'79 300 D 78k (sold)

Open your fuse box. Toward the rear you'll see a small gray 2 pin plug. This is the resistor for the seats. You can open it and have a visual check, it should be burned. Get a replacment from the dealer for about $7.

Vinamg

This resistor is a diode. He is right, it should fix the problem.

__________________
Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS

Ooops, I wrote resistor. It is a diode and I forgot to warn you about the direction of diode. If you by any chance remove the diode from the casing you need to pay attention to the silver line. In other words, you have to be careful not to turn it around.
Not a problem if you purchase from dealer, because it comes with casing. However, I've replaced these in the past with diodes from Radio Shack.

Vinamg

THANKS FOR THE TIP- I'LL GIVE IT A TRY THIS AFTERNOON AND LET YOU KNOW HOW IT WORKS OUT.

__________________
2000 ML430 86k
2000 C280 Sportline 100k
'86 420 SEL 178k
'91 Audi 100 179k
'88 BMW 750il 167k
'83 300 SD 167k (sold)
'79 300 D 78k (sold)

THANKS FOR SAVING MY SANITY- WENT BY THE DLR THIS AFTERNOON-BEST 6.00 I'VE SPENT IN A LONG TIME

__________________
2000 ML430 86k
2000 C280 Sportline 100k
'86 420 SEL 178k
'91 Audi 100 179k
'88 BMW 750il 167k
'83 300 SD 167k (sold)
'79 300 D 78k (sold)