Looking for a bit of guidance. My 95 E320 wagon recently started blowing fuse 7. I've poked around a bit and find that if I turn the ignition switch to ON with the motor unstarted the fuse is OK. If I the motor is running with the key in the ON position (normal started condition) the fuse blows.

I've tried pulling the relays on the aux fans. Same condition. This fuse looks like it covers half the electrical systems in the car, so I was hoping someone might have seen this before and knows of a common cause.

While I assume it's unrelated, the car has developed a bnasty growling sound when the motor is running. Sounds to me like a bearing in an idler pulley failing. Other than the idler pulley, any other common bearing failures on the things driven by the serpentine belt?

Thanks in advance for the assist.

ron

Well, for anyone else who has this problem in the future, here's the cause (at least this time). It was the A/C compressor. The electric clutch assembly apparently started to break down, which was causing the grinding. As well the electromagnet winding of the clutch had failed so when the engine was running something in the winding was apparently grounding out, causing the short which blew fuse 7.

Replacing the A/C compressor has resolved all the problems.