The troubleshooting guide consists of bits and pieces of the posts in the forum. The DIY section should be searched first, then this diesel section, then the "Tech Help" gasser section because the gassers have the same aux fan. Search for "aux fan" or "auxiliary fan" and your model year. AFAIK, the aux fan in your model is turned on only by a pressure switch in the refrigerant line from the compressor. If you are low on refrigerant, the pressure (or is it temperature?) will never get high enough to trigger the switch. There's probably also a relay and a fuse to check. The various threads that your search will turn up should describe all of these, where they are, etc.

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"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
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"Oh lord won't you buy me a Mercedes Benz."
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