I have a 2000 Chrysler Town and Country and I'm trying to troubleshoot my air conditioning, but I'm running into some dead ends.
First off, I get only warm air out of the vents. I checked the compressor to see if it was running, and it was not. The clutch was not engaging at all to turn the compressor. So I thought I had a bad clutch or pulley bearing, but I wanted to first check to see if voltage was getting to the clutch. I checked the connector that plugs into the coil and there was no voltage. So, I went to the relay panel (Power Distribution Center) and unplugged the relay to begin troubleshooting it.
However, before I got into that, I wanted to see if the clutch was working, so I jumpered the relay socket |B| to |D| (see diagram link below) to send power the clutch (engine running, of course). The clutch engaged and the inner ring started turning the compressor. Everything looked good from the outside of the compressor, but I wasn't getting any cold air throught the vents.
This is the part I wasn't sure about. Assuming the compressor and the other parts of the cooling system are good, should I be getting cold air by jumpering it, or does the relay need to be plugged in for the whole system to work?
Aside from that, I still had the problem of voltage not getting to the compressor clutch. So, I started taking voltage measurements on the relay socket and also measurements on the relay contacts with it plugged in. Here's what I got (see diagram for matching letters):
Diagram Link:
http://home.comcast.net/~pjsantavicca/index.html
Voltage Readings of relay socket (engine running):
|A| to ground: 0.04V
|B| to ground: 0.01V
|C| to ground: 14.0V
|D| to ground: 14.1V
|A| to |C|: 13.5V
|B| to |D|: 14.1V
|A| to (+) on batt: -13.5V
|C| to (+) on batt: -0.01V
Relay plugged into socket (engine running):
|A| to ground: 14.0V
|C| to ground: 14.0V
|A| to |C|: 0.01V
I tested the relay on it's own and it works fine. It just does not seem activate when when it's supposed to, when plugged in. I also tested the voltage on the socket when switching on and off the a/c. I got no differences. I did this with something I knew worked, like the high beam headlights, and I got the expected voltage changes.