Hi. If you have any ideas or experience in the 1993 T&C A/C I would sure like to read reply. It will help me keep cool.
I am having an annoying intermittent problem with the A/C system. Sometimes I will set activate the A/C button on the dash but the A/C compressor will not come on for about 2 minutes, or even longer. Usually the radiator fan does not come on either. After a while the A/C turns on and the cabin gets real cold. A/C charge is OK, low side 25 PSI, high side 175 PSI. I am pretty sure it is not low R-134a because the pressures seem just about right and when the A/C turns on it gets delightfully cold. Must be something electrical. Since the radiator fan doesn't start when the compressor is off I am assuming the problem is either the computer or one of the sensors sending bad readings. I assume the compressor clutch is OK. I first want to test the sensors and/or wiring before I blame the computer.
So HOW DO I TEST THE SENSORS? Anybody got a good wiring diagram I can use? All I can find are two sensors.
One is attached to the high-side distribution block mounted on the firewall. I'm assuming that is the high pressure cutoff. What should the normal resistance be? low or high? Is there any way I can hot-wire it to see if that's the problem.
The other sensor is attached to the hose near the lower front by the radiator. It is attached near the accumulator/dryer. Here too, what should the normal resistance be? low or high? Is there any way I can hot-wire it to see if that's the problem. If I remove these sensors, will there be a R134-a leak, or are these attached to Schrader valves to prevent total loss of R134-a?
Any thoughts in hot-wiring the compressor? Good or Bad.
Finally - I think I need to add some A/C oil. All I can find is 'ester oil'. I don't know what is in the system now, maybe ester and maybe PAG. Is ester oil compatible with PAG? What are the drawbacks if the current oil is PAG and I add ester? Opinions please.
HELP - It is getting hot here in Georgia. Reply to this message or send me private e-mail. REMOVE "NOSPAM." from email address below to send to me. gary snipped-for-privacy@hotmail.NOSPAM.com