Ac compressor won’t engaged unless using a wire

[chandlerstovall]

I have a 1996 suburban and I have replaced my condenser and replaced my relay but the only way conpressor will come on is if I use a wire that goes towards the compressor positive in and manually turn it on




I have power going towards pressure switch on the high side and I have power going towards low pressure switch


I tried to jump both pressure switches, and the clutch won’t engage


I even tried to jump the relay and the clutch still won’t engage, but it will only engage if I wire it up with an external wire going into the compressor itself


So can anyone help me figure out what’s going on because the compressor itself doesn’t have power no matter what I do unless I put a wire up to it and bypass all switches.

 

[GoToGuy]

So of course it runs if bypass normal operation . You didn't say what your trying to do? Recharge system? System is full but doesn't cycle? Do you know how the compressor power circuit works? Have wire diagram?

 

[chandlerstovall]

So of course it runs if bypass normal operation . You didn't say what your trying to do? Recharge system? System is full but doesn't cycle? Do you know how the compressor power circuit works? Have wire diagram?

Please tell me

 

[chandlerstovall]

So of course it runs if bypass normal operation . You didn't say what you’re trying to do? Recharge system? System is full but doesn't cycle? Do you know how the compressor power circuit works? Have wire diagram?

I was trying to recharge the system

 

[Schurkey]

First Guess: Open circuit between low-pressure cutoff switch, and compressor clutch. You have power to the low-pressure switch, but even if you jump the switch at the connector, the power doesn't get to the compressor clutch. (Look for power at the compressor clutch connector.)

Second Guess: High resistance in the compressor clutch circuit, there's power but not enough power to properly energize the coil, therefore not enough magnetism to pull the clutch plate in.

 

[monsterwake]

I had to disconnect battery cable to reset my air controller. I fought that for about a year and finally got an old one from an abandoned truck and it works great now. Long shot but maybe your controller needs reset. This is not a normal issue.

 

[chandlerstovall]

First Guess: Open circuit between low-pressure cutoff switch, and compressor clutch. You have power to the low-pressure switch, but even if you jump the switch at the connector, the power doesn't get to the compressor clutch. (Look for power at the compressor clutch connector.)

Second Guess: High resistance in the compressor clutch circuit, there's power but not enough power to properly energize the coil, therefore not enough magnetism to pull the clutch plate in.

There’s no power going to the compressor clutch at all unless you put an external wire crimpled together on the green wire and then it’ll get power that way

 

[chandlerstovall]

I had to disconnect battery cable to reset my air controller. I fought that for about a year and finally got an old one from an abandoned truck and it works great now. Long shot but maybe your controller needs reset. This is not a normal issue.

I don’t think it’s the air controller

 

[GoToGuy]

You were asked if you jumpered the low pressure switch , do have power at clutch?

 

[chandlerstovall]

You were asked if you jumpered the low pressure switch , do have power at clutch?

when I jumped low pressure switch
No power at clutch at all.