1993 GMC C1500 A/C Compressor cycling

[quote:e1c19cea99="mcgway"]Air Conditioning problem
1993 GMC C1500 6 cyl Two Wheel Drive Automatic 99,900 miles
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The air conditioner is cooling as it always has, but A/C compressor is cycling on and off more frequently. Once the inside of the truck cool down, the compressor will cycle on and off every 5 seconds at idle and every couple of seconds at higher RPM. I had heard that the system may be low on R12, but it cools like it always has. I still had a can of R12 and went ahead and added some. It took about 1/2-2/3 of a can. Didn't help, it still cycles rapidly.

I have this truck since new and I know this compressor is suppose to cycle, but it seems to be doing more than it used to. Am I just hearing more things as this truck gets older or is this normal?

Thanks for any help.

Tom[/quote:e1c19cea99]

Check the Cycling Switch.

[quote:33137209e6="obxautomedic"][quote:33137209e6="mcgway"]Air Conditioning problem
1993 GMC C1500 6 cyl Two Wheel Drive Automatic 99,900 miles
----------------------------------------------------------------
The air conditioner is cooling as it always has, but A/C compressor is cycling on and off more frequently. Once the inside of the truck cool down, the compressor will cycle on and off every 5 seconds at idle and every couple of seconds at higher RPM. I had heard that the system may be low on R12, but it cools like it always has. I still had a can of R12 and went ahead and added some. It took about 1/2-2/3 of a can. Didn't help, it still cycles rapidly.

I have this truck since new and I know this compressor is suppose to cycle, but it seems to be doing more than it used to. Am I just hearing more things as this truck gets older or is this normal?

Thanks for any help.

Tom[/quote:33137209e6]

Check the Cycling Switch.[/quote:33137209e6]

Where is this Cycling Switch Located?

Sorry, was at my county job as an EMT got a call. It is mounted on the Accumulator it looks like this....

Here is what the switch look like.....

Thanks. I assume that cycling switch is the same as the "Low Pressure Switch." I had that switch, "Low Pressure switch" replaced a few years ago when the compress just shut down. When the mech. replaced it, the compressor worked fine. So you think this could be the problem? I will go see if the Chev. dealer has it in stock.

[quote:37e08148b9="mcgway"]Thanks. I assume that cycling switch is the same as the "Low Pressure Switch." I had that switch, "Low Pressure switch" replaced a few years ago when the compress just shut down. When the mech. replaced it, the compressor worked fine. So you think this could be the problem? I will go see if the Chev. dealer has it in stock.[/quote:37e08148b9]

To check this jump the terminals in the harness.