W114 Blowing #4 Fuse
 

I recently purchased a 1972 250C. It will run fine for a somewhat short time but then Fuse #4 blows. Once blown the car won’t idle and stalls when put in gear or reverse. Prior to when the fuse blows the right turn signal works but not the left. After blowing neither turn signal works. Any suggestions on tracking down what may be causing the fuse to blow? Also, the emergency flashers don’t work. As a side note there was a white 8 amp fuse in the space when I got the car. I was told by the previous owner to put in a red 16 amp fuse and give that a try.

Kevin Parks
1972 250C
1985 280TE

If the car was delivered in the US, #4 fuse supplies the 4-way signal flasher unit, and the two heating coils for the automatic chokes (front & rear). The front choke heater is supplied directly from the fuse, however, the rear heater is supplied thru a relay which is grounded thru a temperature switch. Whenever there is an opportunity to add a complication to the process, Mother Benz is very likely to have availed herself of that opportunity!

What is the factory amperage spec for that fuse position? Nothing higher than spec should go there.

What is the VIN? 114.0x3 12 xxxxxx

"Once blown the car won’t idle and stalls when put in gear or reverse."

This description matches a 280, not a 250.

FYI there are two threads on the same topic, this one and one in the Vintage forum.

Frank Reiner, my '71 250 (not "C") has a 2.8 engine. I am not sure if the same engine is in the 250C? While I am sure there was a good reason for Mercedes to do use the misleading nomenclature (product differentiation?), it is indeed confusing.