[Pickles]

a friend here at work has a 1997 chevy suburban with 350 engine, when she turns the truck off, the air cond blows the fuse. the air cond works fine while she is driving. but blows the fuse everytime she turns it off. what do you all think it can be.

thanks, Pickles

[73oldsman]

Now that's a new one! Is it the correct size fuse the manual calls for? Have they tried turning off the AC before killing the truck, which should keep from blowing the fuse when shutting the vehicle off? At least that way they will have a working AC system. I had a Nissan years ago that kept blowing the fuse at different times intermittently, which I swapped out the AC relay for another similar relay under the hood and cured the problem. I hate to do swaptronics, but if it's the AC relay fuse that's blowing, you may try swapping it out first. Otherwise they may need to take it to a reputable shop for troubleshooting. Let us know what is found to be the culprit please.

[BWTRH]

first i would check the relay but also there should be a diode across the compressor clucth plug the prevent a high amprage spike when the clutch shuts off. the reason the fuse only blows when the truck shuts off is because the truck probably has a variable displacement compressor which does not cycle like your typical a/c compressor. it has a wobble plate inside the compressor that verys the pressure. but i would still refer to a motors repair manual and check the wiring diagrams