Attention: TDR Forum Junkies Hey guys, I just did a little troubleshooting and repair on the A/C system in my 93. Fortunately for me the freon level was still very good. My problem was in the electrical system. I took some pics that I will attach best I can. Anybody that has anymore incite please feel free to add, and maybe Pastor Bob will add this to the sticky list.
I was having intermintent a/c performance, in the yard it would blow a consistent 35*F air from the ducts, but start down the road and it would come and go. I finally dug out my FSM and started digging into the electrical as I already knew the freon level was good. First I located the Wide open Throttle cutout relay. It was on the drivers side inner fender, the rear most one.
#ad
Then I bypassed it with a jumper wire with spade ends crimped on it.
#ad
This allowed the compressor to run continuously. I only did this for testing to see if the WOT relay could be causing the problem. *WARNING* if you bypass the relay like this, the low pressure switch, and temp probe hooked to the A/C cycling switch will not be effective. The compressor will run until the compressor seizes due to freeze up, or lack of freon/lube. I hooked the relay back up the way Dodge intended and went on about my way.
Next I let the truck run, with the windows down and the A/C on. With the windows down the A/C system thinks the cab is not getting cool and will run at full potential. If the windows were up, the cab would eventually cool down, and possibly let the compressor cycle more intermintantly. I watched the compressor clutch to make sure it was turning(ie engaged). I pulled the probe out of the low pressure line and found that my compressor would disengage, when the wires on the end of the probe were tugged on. Before removing this from the system I bypassed the low pressure switch like this and rechecked the probe for problems.
#ad
With the low pressure switch bypassed, I was still having problems with the probe connection. I hooked the low pressure switch back up and then removed the A/C cycling switch from the truck, cut open the plastic connector and found this.
#ad
As you can see, the connection had lots to be desired. So I got the soldering gun out, repaired the connections to the best of my Ability, and covered the individual wires with shrink wrap. Then I put some larger shrink wrap around both wires for a little more strength. These two wires need to be insulated from each other or the a/c system will in certain conditions freeze up. The temp probe prevents this from happening.
#ad
#ad
Now I am not a good soldering gun operator, so I will be replacing the A/C cycling switch for a more permanent repair.
Here is a pic with the A/C cycling switch installed and the probe inserted.
#ad
Here is a pic of where the A/C cycling switch, low pressure switch, and h block are located under the hood.
#ad
**PLEASE NOTE** The relays/ switches I bypassed were for testing purposes only. A person could bypass any of these to make the A/C work temporarily. When any of the safetys are bypassed the system can freeze up, ond get overpressurized, or the compressor could fail from lack of lube carried by freon if the level is low. Everything I did to bypass was temporary.
Michael
I was having intermintent a/c performance, in the yard it would blow a consistent 35*F air from the ducts, but start down the road and it would come and go. I finally dug out my FSM and started digging into the electrical as I already knew the freon level was good. First I located the Wide open Throttle cutout relay. It was on the drivers side inner fender, the rear most one.
Then I bypassed it with a jumper wire with spade ends crimped on it.
This allowed the compressor to run continuously. I only did this for testing to see if the WOT relay could be causing the problem. *WARNING* if you bypass the relay like this, the low pressure switch, and temp probe hooked to the A/C cycling switch will not be effective. The compressor will run until the compressor seizes due to freeze up, or lack of freon/lube. I hooked the relay back up the way Dodge intended and went on about my way.
Next I let the truck run, with the windows down and the A/C on. With the windows down the A/C system thinks the cab is not getting cool and will run at full potential. If the windows were up, the cab would eventually cool down, and possibly let the compressor cycle more intermintantly. I watched the compressor clutch to make sure it was turning(ie engaged). I pulled the probe out of the low pressure line and found that my compressor would disengage, when the wires on the end of the probe were tugged on. Before removing this from the system I bypassed the low pressure switch like this and rechecked the probe for problems.
With the low pressure switch bypassed, I was still having problems with the probe connection. I hooked the low pressure switch back up and then removed the A/C cycling switch from the truck, cut open the plastic connector and found this.
As you can see, the connection had lots to be desired. So I got the soldering gun out, repaired the connections to the best of my Ability, and covered the individual wires with shrink wrap. Then I put some larger shrink wrap around both wires for a little more strength. These two wires need to be insulated from each other or the a/c system will in certain conditions freeze up. The temp probe prevents this from happening.
Now I am not a good soldering gun operator, so I will be replacing the A/C cycling switch for a more permanent repair.
Here is a pic with the A/C cycling switch installed and the probe inserted.
Here is a pic of where the A/C cycling switch, low pressure switch, and h block are located under the hood.
**PLEASE NOTE** The relays/ switches I bypassed were for testing purposes only. A person could bypass any of these to make the A/C work temporarily. When any of the safetys are bypassed the system can freeze up, ond get overpressurized, or the compressor could fail from lack of lube carried by freon if the level is low. Everything I did to bypass was temporary.
Michael
Last edited by a moderator:
