FIXED, see second paragraph. Now i have a new problem LOL.

I have a 1993 USDM, I have a haltech 1000 and installed the JP3 AC line kit. I can't get the Haltech to switch on the compressor. I grounded the AC request as I saw from searching but that didn't work. When I turn on fan and AC button, I see zero change in voltage on the Haltech, with it grounded or not. All wiring from ECU to fan relay works. Only thing I can think of is that I removed my instrument cluster because I'm using a CD5. I thought grounding the request would bypass that. Any other suggestions or tests I can try???

FIXED
I got the AC output to work in the Haltech when fan switch. Now I'm getting no voltage at pressure switch.

 

does the request actually trigger in the ecu? if not it will never turn on the compressor

 

Yes it's triggering in the ECU. I just get no voltage at the pressure switch. AC relay works. I'm thinking it's the wiring at the pressure switch. One end should go to AC relay and other end should go to compressor, correct? I'm not sensing continuity from one end of the switch.

 

How do you have your wiring setup? On my fc, input signal: ECU>pressure sensor>thermostat>HVAC unit. HVAC unit grounds when fan and A/C button on. Output wire to relay that operate the fan and A/C clutch

 

Have you checked the relay?