need some help guys,im fixn my grandmothers friends 1994 sedan deville,74k,well maintained..she wanted new compressor,dryer,orfice,also replaced high & low pressure switches.charged system by hot wiring compressor..
my problem is the compressor will not come on,ive cked fuses,relays,double cked pressure switches,have disconnected batt & held pos & neg cables together for 5mins to reset..if i ground the green/white wire at the compressor relay the compressor engages and system cools fine....need to know where to go from here......thanks for any info you give me...

(Droidx)

Jump the low side switch with a paperclip.

I've jumped low switch,high switch,temp switches,changed relay,still no compressor clutch....

But you can still put 12v to the clutch and it will turn on?

I can give the relay a ground(green/white wire) & all works good,I put 12v to clutch with jumper wires to charge system...

Either something is wrong with the HVAC controls inside the car, or the PCM is still seeing a reason not to turn on the compressor. Can you reinstall the old switches to see what happens?

I could but it was doing same thing before I changed them..

Even though you said you charged the system, make sure it'* holding that pressure. Start the car and put your gauge back on the low side fill port. If you have less than 35 psi, the compressor will not kick on no matter what you do.

Its holdin pressure,just double cked it...

Could this $450 control head be my problem? It some times comes right on(blower motor runs & digital read out shows temps) & some times it shows "--" instead of temps & blower motor won't come on,also shows front defrost is on,will stay this way for about 60 to 90 seconds & will not let u change anything,turn off,etc.. then shows temps & blower motor comes on...