A.c. compressor non stop runs

[Albert]

I have a 98 extended cab I'm having a issue with the a.c. compressor it always runs non stop I changed the hvac switch out no luck also pulled the switch on the accumulator an no luck either pulled the relay finally stopped anyone have this same or similar issue? Compressor was new when I bought the truck maybe I need a new Compressor?

 

[Albert]

Anyone?

 

[97redz71]

My compressor is literally doing the same thing.

 

[Albert]

My compressor is literally doing the same thing.

I can't seem to trace out the problem refrigerant is low cause I have a leak somewhere but I can't seem to find any info for a compressor non stop running it's driving me crazy. Any input would be great lol

 

[delta_p]

Shop manual diagnostic for my '96 says if the A/C compressor is operating continuously, check for a short to ground on "dark grn/wht wire (459). looking at the schematic, this is the wire that goes from the A/C compressor clutch relay "coil" to the vehicle control module. if this wire were shorted, would throw the relay and allow the clutch to engage when in run or start regardless of the VCM control.

 

[Albert]

Ok thanks I'll check that out

 

[delta_p]

Ok thanks I'll check that out

also that clutch cycling switch at the accumulator should close at about 46psi and and allow the clutch to engage, and open at about 25 psi to disengage. if you don't have the right charge or for some strange reason i couldn't possible imagine the orifice tube got left out, that would also cause the clutch to engage because the switch wouldn't cycle.

 

[delta_p]

pulled the relay finally stopped

check the relay isn't stuck too. Good luck.

 

[Albert]

check the relay isn't stuck too. Good luck.

Swapped relays and didn't work I know the system is low because there isn't any cooling could that cause the compressor to always run?

 

[delta_p]

Swapped relays and didn't work I know the system is low because there isn't any cooling could that cause the compressor to always run?

usually it doesn't cycle at all, or cycle on/off rapidly. Does the clutch disengage when you turn off key? do the clutch disengage when you pull the connector off the cycling switch at the accumulator? So the only other thing with no cooling and compressor on...no orifice installed, restricted suction line something like that would that prevent the switch from going low enough pressure to open.