Arthur,

As usual, insightful and to the point. I just posted about our 300 e which overheats when AC is on. After reading your post, how simple it was to go out, jumper the press switch leads and watch both fans spin opposite the arrow directions. These were real ACM fans not e bay specials.

Unbelievable, the connectors are not reversible, so how can they go backwards? This really explains the overheating when the AC is on, ie. the aux fans must kick in, counteracting the engine mounted fan, and things go from warm to hot. When the temp climbs higher and the aux fans go to high speed, it actually makes things worse.

Wow, what an eye opener.

Thanks,

Martin Wolf