AC, cruise control are not working

1998 PONTIAC FIREBIRD
74,000 MILES • 5.7L • V8 • 2WD • MANUAL
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FIREFIGHTER285
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No codes when use reader. AC compressor does not come on when AC selected. Vents and heat work.
Apr 1, 2019 at 1:28 PM
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JOETECHPRO
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Hey FIREFIGHTER285,

There is a fuse which covers both A/C clutch and cruise control. Most likely your issue.

15A mini fuse.

In the under hood fuse box 2.

I have attached the locations.

A guide to checking fuses below.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Hope that helps, let us know how you get on.

Regards, Joe
Apr 1, 2019 at 4:56 PM
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FIREFIGHTER285
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Thank you Joe for the quick reply. After I posted my question I looked further into it and found that fuse to be undamaged. I also replaced the AC resistor in the same box. AC still does not work. The cruise control worked one time after replacing the AC resistor. However, I don't know if that is the reason why it worked I guess there could be some kind of short in the cruise control. I can't see a reason why the cruise control would work after replacing the AC resistor. Still searching for a reason why AC does not come on.
Apr 2, 2019 at 8:46 AM
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JOETECHPRO
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Hey Firefighter285,

Do you mean the A/C relay in that box?

After replacing the relay did you recheck the fuse?

Do you own a 12 volts test light or a multi-meter?

Regards, Joe
Apr 2, 2019 at 10:13 AM
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FIREFIGHTER285
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I did not recheck the fuse, but I will. I should also say that maybe the AC and cruise are not related. I plan to get under the dash and look to see if there is a switch or button on the clutch pedal that needs adjusting/replacing that sends signal to cruise. it may be intermittent because of something like that. Yes, I own a multi meter, and ordered a test light. I am not very familiar with using either, but will watch a few videos to get caught up. Do you think I should start at that fuse box and see if the 15A fuse is getting power? Any help you could give me whether to have car running/not and AC selected or not would be great. I should also say that I have to do this work outside and we are about to get three days of straight rain. The car is in immaculate condition with 45,000 miles. I bought it seven months ago at an auction and when I got it the AC and cruise didn't work. It has been on my list to sort out. Thank you Joe for your help.
Apr 2, 2019 at 8:17 PM
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JOETECHPRO
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Hey Firefighter285,

The first test will be to check you have power both sides of the fuse.

The guide i sent you before is great to run you through how to do this.

This fuse is only powered with ignition on/engine running.

Once you are happy you have power to both sides of the fuse we can then run through further tests.

Regards, Joe
Apr 3, 2019 at 9:00 AM
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FIREFIGHTER285
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Thanks Joe, will let you know what I find.
Apr 3, 2019 at 5:55 PM
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JOETECHPRO
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Hey Firefighter285,

The test light is useful as it tests for voltage drop/load tests wiring easily and is visually easier to use than a multi-meter.

You do have to be a bit careful what you are testing.

For fuses the test light is great.

Let me know how you get on.

Regards, Joe
Apr 3, 2019 at 6:00 PM