Last night I was able to see the compressor work. Here is what I did: Since I can not find a pressure switch by the accumulator, I jumped the other one (from my earlier post), there are 3 wires on it red, tan and black. When I jumped between the red and tan wires the electric fans come on. I checked the compressor for voltage and had none. Leaving the switch alone, I connected a wire from the A term on the compressor to + on my battery (nothing) and then from the B term to ground and low and behold the compressor came on. Compressor sounds good..no noise etc. But....I got no cool air in the car. I ran in this condition for about 5 minutes. I think I will go pick up a recharge kit tonight and give it some more 134a. Are the kits from say.....Autozone reliable? I also have an Advance Auto parts close by. If that doesn't fix it I don't know.

Just make sure it'* a synthetic, and don't rely full heartedly on that gauge.....

The fact that the A/C refridgerant is low could be the reason for your troubles.

Problem solved! I went back and read everything again and decided that maybe the compressor needs to be running to properly fill the system. Well, that did it. I bought a 19 oz can of R134a / lube/ sealer, jumped the compressor to get it going and started filling. The cheap gauge that came with the kit showed a little over 30psi when I was done. It took about the whole can and now is blowing nice cold air. Hopefully there is no major leak and it stays charged for a good while. Thanks to everyone for your help!!!

When doing a system like you had,soaking the can in hot water wile discharging
will alow it to take with out running the pump,,,doing that you can damn
near fill the system with out ever running the pump.....

actually that'* how i was tought many moons ago,,by a vary smart man

One of the conditions for A/C clutch engage permissive is low suction cut out switch satisfied. (closed) Adding R134a will remedy this situation, but you will have to defeat the switch to add refrigerant which is what you did. Congratz! Nice job viola, cool air at the A/C outlets.

Help! I followed this instruction on my 92 Bonneville SE and grounded the connector going to pin 85 on the relay. Before I did this I was reading 12 V on it. Afterwards, it only read around 8 V. I then looked at the relay and noticed a circuit diagram showing pins 85 and 86 as the input to energize the relay. The pins that are actually connected by the relay when active are 30 and 87. I then used a jumper from the + terminal of the battery to the connector to pin 87 and my compressor ran. I was able able to fill with R134A this way since the car had been converted previously.

Now, the problem is that even with the pressure correct (35 psi on the low side and 180 psi on the high side when running at max), I can only run my AC with the jumper on. When I connect the relay, the compressor still won't come on. I'm afraid that I might have damaged something by grounding the connector to pin 85. I also read 12 V on the connector to 30 before I grounded 85. Unfortunately, my Chilton shop manual doesn't have schematics for the AC so I don't know what to do now.

Thanks in advance for any help.

You may wish to check the maxi-fuses on the firewall to make sure none of them blew. There is one specifically for the A/C.

Thanks for the reply. The blower is running so it wasn't the maxifuse (30A). Instead, I found a 15A mini fuse under the glove compartment that was blown. Based on a circuit diagram that I found on the web (http://www.gearchatter.com/viewpost14020.php), I figure that the 12 V supply that drives the AC clutch goes through this fuse. The circuit is probably not the exact one for my car since the location and value of the fuse is different but it'* very close. I haven't replaced the fuse yet since it was late at night and I couldn't find a spare one to use. I hope everything works once I replace it today.

I replaced the fuse and the compressor isn't coming on with the relay connected. I verified that I'm getting 12V to the relay terminal 85 and 30 with the replay disconnected and the car running with the the AC set to MAX. If I put a jumper across 30 and 87 (the wire to the clutch), the compressor comes on. I'm suspecting that something is wrong with the PCM/ECM or one of it'* input is not right. BTW, I already checked the low pressure cut-off switch on the accumulator/receiver with a multimeter and it'* working fine (short). Any other possibilities?

Thanks again.

I read the ECM trouble codes and found error code 66 (indicates AC is cycling too much due to low freon). I reset it by unplugging the - battery terminal for >15 seconds. Afterward, the AC is started working. In summary, the problem was originally due to low freon. But in order to run the AC again, I had to reset the ECM. In the process, I blew a the fuse that supplies power to the compressor clutch.

This tread was really helpful to me. Thanks to everyone who has contributed to it in the past.