300e 1991 Gauges out, buzzing all the time
 

This is not my car, but for a friend.

The following problems are taking place.....

1-No Gas Gauge,
2-No Tachometer,
3-No Temperature reading,
4-Some of the other lights (coolant level, windshield fluid level, light warning..etc) never come on even at the first turn key...
5-The buzzer noise does not stop after the car has started and even when the seat-belt is in place. it only stops when the turn signal is on, but comes back again when it is turned off)..
6-Half of the cluster is dark (no light)

So what is the problem? and what should i start looking at?

thanks,

Fuse 5 or 6

This is the time to remove all the fuses and replace ALL with fresh ones. The contact tangs have to cleaned before installing the new fuses. Brass ones are best ,in a kit .
This will save you a lot of intermittant electrical faults caused by to aging and micro cracks in the aluminium fuses.
mak

86 300E fuse #5. Fixed. Thanks!