1988 Comanche AC won't turn on, can't locate fuse?

[Shozam]

Hello Comanche forum!  I am writing this for my dad, who I signed up but is now busy mowing the lawn. I'm going to do my best!

 

1988 Jeep Comanche 4.0l with automatic transmission. We *think* it is factory installed air.

 

My dad had his air conditioner fixed two years ago and it worked great! He needed to have the system sealed and recharged, and all has been well for two years

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Right now, when he turns on the AC, nothing happens. He does not even hear the compressor kick in, which it would before the sealing and recharging of the system. He thinks that it may be the fuse is bad, since he doesn't hear the compressor kick in at all. everything else works, blower, heat etc..

 

Following the Chilton guide, we see fuse 17 (7.5 amp) listed for "heater and ac' in the power distribution center, but can't find where this PDC is located. He does have fuses under the hood but the one that runs to the compressor is 12 amp. We are hoping it is the fuse, but aren't sure if the 12 amp fuse which seems to go to the compressor is the right fuse.  Or, should we should be looking for a different inline fuse if it were a factory install?

 

I'm attaching two photos of the fuses we DO see under the hood.

 

Can anyone help me with this? Any suggestions welcome.

 

 

 

 

 

 

 

 

[Marine1Texas]

is your blower coming on at all? if not that is a 25 Amp Blower Motor slot 3.  Take your relay out , clean connection. From there you can also jump the compressor to see if it is working. Also with your volt meter check to see if your getting power to the relay.

 if everything is working check to see if the pressure switch is not allowing the compressor to come on because of low Freon level. get your self a gauge to test you low side pressure. if it is below 10 psi that could be the reason, also some times bad pressure switch's can happen.

 

This is the electrical wiring for it

[Shozam]

Thanks! I'm going to have my dad read thru your suggestions and see what he finds.

 

Much appreciated!

[Shozam]

I took out each of of those relays and cleaned them all since I was in there. 

 

Still no A/C. After cleaning, I still couldn't hear the compressor starting to operate when I turned the a/c on. The engine still ran as normal, no indication engine was turning compressor, no RPM speed-up or anything. I did hear the electric fan turning on, but not the compressor.

 

All those relays I have look like original connectors, by the way.

 

I am going to replace the A/C Clutch Relay and see what happens.

 

If this doesn't work, can you explain how to jump the compressor? I'm not sure what you mean by that or how to do it.

 

I'm going to replace the relay first, try jumping the compressor next and go from there to check the freon pressure as you suggested. Hopefully it is just a bad relay, but would like to know how to jump the compressor just in case.

 

Thanks!

[cruiser54]

I took out each of of those relays and cleaned them all since I was in there. 

 

Still no A/C. After cleaning, I still couldn't hear the compressor starting to operate when I turned the a/c on. The engine still ran as normal, no indication engine was turning compressor, no RPM speed-up or anything. I did hear the electric fan turning on, but not the compressor.

 

All those relays I have look like original connectors, by the way.

 

I am going to replace the A/C Clutch Relay and see what happens.

 

If this doesn't work, can you explain how to jump the compressor? I'm not sure what you mean by that or how to do it.

 

I'm going to replace the relay first, try jumping the compressor next and go from there to check the freon pressure as you suggested. Hopefully it is just a bad relay, but would like to know how to jump the compressor just in case.

 

Thanks!

See the low pressure switch on the receiver-drier behind the compressor?

 

Unplug the harness from the switch and jump it with a paper clip and see if the compressor engages. If it does, the system lost it's charge. don't leave the paper clip in there.