Help: M1152 A/C Condenser Fan Not Blowing / Compressor Not Engaging

[TXManka]

Need help. The fan blows when the A/C is on but neither the condenser fan not the compressor engage.

I’ve unsuccessfully tried to locate an M1152 electrical diagram showing the condenser fan and compressor circuits. Is there a circuit breaker in line that would cause these two items to not function? Any other troubleshooting recommendations?

 

[HoveringHMMWV]

From forums @ G503.com. Hope this helps.

 

[Mogman]

The system has to have freon in it to work, have you put gauges on it?

 

[TXManka]

The system has to have freon in it to work, have you put gauges on it?

I did. The A/C had been running fine before it quit. It seemed odd that both the compressor and rear condenser fan wouldnt come on when I turned the A/C switch on (the blower fan works fine). I put a gauge on the low pressure side (I don’t have a full gauge set, just the A/C fill gauge to get at auto zone) and the pressures were high so I opted to remove coolant until the pressure was in-range thinking the high-limit switch may be cutting off the circuit. I also bled pressure off the high side to normalize it. Now that the low pressure side is reading normal, the condenser fan still doesn’t kick on.

I am going to grab a full gauge set today to check the pressure on both the high and low side. I suspect either the circuit breaker or a limit switch is tripping still.

 

[TXManka]

From forums @ G503.com. Hope this helps.

View attachment 897066

Thank you!

 

[Mogman]

I did. The A/C had been running fine before it quit. It seemed odd that both the compressor and rear condenser fan wouldnt come on when I turned the A/C switch on (the blower fan works fine). I put a gauge on the low pressure side (I don’t have a full gauge set, just the A/C fill gauge to get at auto zone) and the pressures were high so I opted to remove coolant until the pressure was in-range thinking the high-limit switch may be cutting off the circuit. I also bled pressure off the high side to normalize it. Now that the low pressure side is reading normal, the condenser fan still doesn’t kick on.

I am going to grab a full gauge set today to check the pressure on both the high and low side. I suspect either the circuit breaker or a limit switch is tripping still.

The low side is always going to read high when the compressor is not running, you will need to replace the freon you blew out, I have never seen an ac get too much freon unless someone puts it there.
You should be able to go through the schematics and figure out where the circuit is disrupted, the compressor and condenser fans come on together so very unlikely a problem with both at the same time.