Here I am

A/C issues. Need help.

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Trailer lights inop

2007 Fog Lights

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Is this with the magnet plugged in? I use push pins to backprobe the connector. If the magnet isn't plugged in when taking a voltage reading any high resistance connection will not be found. (Reads good voltage unplugged with no current: plug it in and voltage drops like a rock to near 0 with a high resistance connection.)

An ohm test of the magnet will also answer questions. Keep in mind to measure it both ways as there may be a diode built in to the magnet.
the magnet is about 5 ohms. There is no diode. It measures the same when changing polarity. When back probing the connector with the magnet connected I get 0 volts. When I unplug it it jumps to 11.49v. I checked the gap again. 15'''. I smacked it with a small dead blow hammer to see if it would engage but it did not. Not surprising with 0v on the magnet.
 
So like the "lamp out" indicator it may have a zero amp sense voltage on it and something else is not turning the A/C system on. Or it's got a high resistance connection somewhere. What is the voltage to ground? This could indicate a bad ground if it has voltage to ground with the coil plugged in. Otherwise you will have to trace the wiring looking for a relay etc.
 
So like the "lamp out" indicator it may have a zero amp sense voltage on it and something else is not turning the A/C system on. Or it's got a high resistance connection somewhere. What is the voltage to ground? This could indicate a bad ground if it has voltage to ground with the coil plugged in. Otherwise you will have to trace the wiring looking for a relay etc.
It's starting to look like a TIPM problem. I am going to try putting a relay on the connector for the magnet to see if it has enough power to energize it. The relay in the TIPM seems to be the problem. It kinda works but when drawing current it falls flat on its face. I haven't found a resource that tells what relays in the TIPM are for what functions. It would be quite a chore to try and figure out witch one is for the AC.

<RANT> Why would Chrysler solder all of the relays to a board sandwiched between other boards with hundreds of very fragile pins that must all be lined up perfectly and not protect any of them with fuses? Every other manufacture has the sense to use standard automotive relays that can be easily and cheaply replaced. Chrysler makes it all one unit that is expensive to repair and insanely expensive to replace. </RANT>
 
Dorman TIPM is on the way. I had a 20% coupon code for AutoZone bringing the price with tax town to $370 + $300 core charge. I had some other problems with my TIPM that I was bypassing to make things work. I finally broke down and got this one instead of doing another work around.
 
Well, TIPM didn't do it. Still no juice to the a/c clutch magnet. I started digging deeper. I'm going to try graphing a/c pressure on alphaOBD. I hope it can read and graph it. That will tell me if I have a problem with the pressure switch. I may have to trace the wires through the harness to get to the bottom of this.
 
Update. AC pressure is low. It's the cold season now. I am going to have to take it to an AC shop. If the pressure is low, then I definitely have a leak. Probably the compressor. I suspect it got pretty hot when the clutch bearing burned up. If it isn't low, it must be the sensor.
 
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