Can someone steer me what to look at when the #2 fuse (compressor / Aux. fan) shorts.

I can feel the compressor kick on then the fuse immediately pops. I jumped the auxillary fan and it spins. Any idea what the draw on the auxillary fan should be?

Checking the A.C. relay the next step?

Thanks.

Tinker

The draw should be less than the amp rating of the fuse.

Unplugged the auxillary fan and ran the compressor, no problems. I would appear the fan or one of its relays is the culprit?

Tinker

MMMmm Pretty rare for a relay to have enough resistance to blow a fuse. And if it did, it usually would not work. However, your aux fans are high amperage motors with high exposure to water/corrosion. I'd put my money on the aux fans every time. They can appear to work fine but still be drawing too many amps.

I'd say it's much more likely the compressor clutch is the overload, rather than the fan motor. Unplug the fan motor, then try turning on the AC. I suspect the fuse will still blow. If that happens, I suspect you will find charred insulation on the clutch coil windings.

Steve

__________________
'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7

When checking for shorts, I have taken a fuse and soldered the stripped ends of some wire on the ends and connect it to a 2 pole turn signal flasher unit. the flasher takes the electrical load and lets you unlpug stuff until it stops clicking, then you have found your culprit, without using up a bunch of fuses.

That brings me to my similar problem:
1993 190e 2.3, blowing fuse #1. I have mitchell-on-demand with its limited information, and have unplugged everything I can find that is related to that circuit.
Does anyone have experience removing the fuse box, I cant seem to find the forward bolt from the top side (I can see it from the bottom) I feel that my short is in the the box itself, and is this a common problem?

Thanks,
--Dan Zipkin

I found my short. It was a pinched wire at the aux relay box bracket. Just the result of sloppy work by a previous tech.

Tinker, It seems that you are on the right track

--Dan

Thanks for the feedback everyone.

I've read and been told that if the auxillary fan spins freely and runs when jumped, it is probably not the problem. The car has only one and the draw on it does not appear excessive

Which leads me to Steve's suggestion of the compressor clutch. The clutch has been making noise for some time.

Dan, thanks for fuse bypass suggestion. A buddy has a similar setup and I was trying to think of what he was using to take the temporary load, that flasher.

Tinker

As a follow up;

Juggled the relays around and reconnected the auxillary fan and everything is working normal. Corrosion on a connection or a bad relay? Or the clutch pack?

Never ceases to keep me guessing.

Tinker

I have the same problem of the fuse blowing when the aux fans kick in. Where is the relay you mentioned at?

There is a separate small covered fuse box next to the main fuse panel.

My joy was short lived, it's popping #2 again. Time for some AC ($$$$) work.

Tinker