I have a 93 190E that seems to have a short in the electrical system. The radio goes on and off about every three or four days. When it comes on, it stays on for a few days and when it goes off it stays off for several days at a time.

The dome light and the clock mirror the radio. They are either all on or all off. What is even stranger is that the dome light does come on when you open the back doors (but not the front)

Any suggestions on what would cause this problem and what needs to be done to correct it?

You are not dealing with a short circuit, you are dealing with an intermittent open. There is a flaky connection somewhere in the power feed circuit that is common to all these accessories. I would start with the fuse.

You can determine that a fuse is bad by looking at it, but you cannot always determine that one is good by looking at it. Sometimes it will be broken and intermittently make continuity. I would find the fuse, remove it and tap on it while doing a continuity test. If it occasionally does not make continuity while tapping on it, replace it. If this happens, make sure you throw the fuse away to prevent it from driving you nuts later on.

If you find no problem with the fuse, trace the connections from the fuse and wiggle them along the way to see if you find a point where wiggling it makes the accessories go on and off. If you do, you have found your problem.

Good luck,

Had the same problem.

Checked the fuse and it looked ok.

Swapped it out and the radio/clock/etc have not faltered ever since.

Closer inspection of the fuse (Euro type) revealed that it was slightly damaged at the ends.

Try it out. Cheap fix if it works.

Azhari
1991 190e 1.8
Singapore