'91 Olds 98 Regency, 3800, 226k miles.
My ac was only moderately cooling on the hwy and not at all in town. I pulled the orifice tube and discovered it was terribly clogged. I pulled the compressor and it had very little pump and suction. Therefore, I replaced the comp, accumulator, condensor etc. I vac'd the system for an hour. The compressor would not start while I was refilling w/ 134A. Then grounding the cycling switch leads with the old paper clip would not start it. Switched the relays around with the horn relay. No luck (jumping the relays to the battery produced the proper clicking of the relay). Then I ran a jumper from the + battery terminal to the light blue lead on the cycling switch lead and wa-la the comp. Sprung to life along with the cooling fans. I then grounded the refrigerant pressure switch on the back of the compressor, and grounded the high pressure switch that is in-line on the high pressure line. No luck. I tested the controller unit and the ECM and found them both to be working fine. I'm at a loss now for the reason I have no " juice" at the cycling switch connector and the old paperclip diagnostic tool will not bring it to life. It was all working fine before I " fixed" it. What else could it be? What should I check now. ALSO, I've noticed on my AutoXray, that even when I press the Auto AC button on the dash, the scanner still indicates " AC Not Requested".