started air conditioner & blower - fuse 5 blows

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Animal Lawyer

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Was driving with air on, suddenly it goes dead. checked fuses #5 blown. replaced it and turned on air  & blower again, fuse blows. Any suggestions on how to troubleshoot this.

 
I would start by eliminating possible sources of the problem. I like to start with the easiest, disconnect the compressor clutch under the hood and see if it still pops the fuse, just running on the blower, if it does then it's likely something failing in the blower motor. If the fuse doesn't blow, the problem is likely the compressor. My first suspect is the windings in the compressor clutch shorting out.

It's also possible one of the wires has compromised insulation and is shorting out. More difficult to trace, lets you find out what kind of contortionist you could be. 

 
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It may be something really stupid on my part. What should the amperage be for fuse 5? After it blew I googled it and got a response of 10 amps. When I went to the shop manual last night, after getting home, I read it to require a 30 amp fuse If I put in a fuse rated 1/3 the necessary,....

Serves me right trying to diagnose problems in Municipal Court parking lots!

 
When you have air conditioning it requires a 30 amp fuse. Without air conditioning it would be 14 amps.

But, why did it blow in the first place? Possibly due to corrosion inside the glass tube, which is common, which would cause resistance and heat. 

 
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