As I understand it, the AC temperature switch that attaches to the dryer causes the Aux fan to kick in when the refrigerant reaches a certain high temperature to get additional cooling. I had my AC serviced today and this temp switch broke off when my indy tried to remove it from the old dryer. As it was late Friday, he said I could replace it myself rather than have the car sit there until Monday. So what I am asking is, should I jump the leads on the dryer so the aux fan comes on all the time to get additional cooling? If I do this, will the aux fan only come on when the compressor engages? The other alternative is too spend the $45 to buy a new switch. Thoughts +/-?

The question may be similar to whether or not to buy a new change over valve or tie the boost line directly to the ALDA line bypassing the need for the chang over valve.

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The aux fan is not in the compressor circuit. If the switch is jumpered, the fan will run whenever the key is not in the OFF position.

If you were so inclined, rewiring the fan relay into the compressor relay circuit would be a simple task.

So for these hot summer days I can just jump this switch without worrying about overloading until I get my new switch?

You could.

The fan draws considerable current, however. The battery will suffer if the fan runs full time at very low engine rpm's for an extended period.

If the threaded portion of the switch broke, it might be possible to do a little drilling and tapping and put the old switch back in action.

I tried that with WD40 and a drill but it won't dislodge and I don't what to mess up the dryer. Thanks.