Attention: TDR Forum Junkies 
ChrisWilliams
TDR MEMBER
Hi folks,
I just purchased a 91 250 CTD 4x4 this week and am working on a little AC problem. I have been browsing this site for a while finding good information and haven't had a need to ask for more info since there is so much already out there. I found a good thread about this titled "No Power to A/C", but I didn't see the test procedures I was looking for.
With my AC on max, the compressor will not kick in. There is a "temperature sensor/clutch cycling switch", not sure what it is called, with a three wire connector ( brown (hot), blue (hot), blue/white (ground) ). If I unplug and short the brown and blue/white wires, the compressor kicks in and blows cold air. My gauges read 40lbs from the low side and the low pressure switch, against the firewall, is giving continuity. I think this temperature sensor switch is bad, but I don't have a FSM yet and don't know how to test it. Does anyone know exactly what this switch is called and/or have test procedures for it? I have attached a picture of it. I googled the part number (56005783) and came back with a site in Mexico with the part "THERMOSTATO ELECTRONICO PARA RAM CHARGER". I am guessing this translates to electronic thermostat. If this thing is bad, how am I going to change out that temperature probe which is hard wired to the box and sticks right into the line? I would appreciate any info you guys can send my way.
I just purchased a 91 250 CTD 4x4 this week and am working on a little AC problem. I have been browsing this site for a while finding good information and haven't had a need to ask for more info since there is so much already out there. I found a good thread about this titled "No Power to A/C", but I didn't see the test procedures I was looking for.
With my AC on max, the compressor will not kick in. There is a "temperature sensor/clutch cycling switch", not sure what it is called, with a three wire connector ( brown (hot), blue (hot), blue/white (ground) ). If I unplug and short the brown and blue/white wires, the compressor kicks in and blows cold air. My gauges read 40lbs from the low side and the low pressure switch, against the firewall, is giving continuity. I think this temperature sensor switch is bad, but I don't have a FSM yet and don't know how to test it. Does anyone know exactly what this switch is called and/or have test procedures for it? I have attached a picture of it. I googled the part number (56005783) and came back with a site in Mexico with the part "THERMOSTATO ELECTRONICO PARA RAM CHARGER". I am guessing this translates to electronic thermostat. If this thing is bad, how am I going to change out that temperature probe which is hard wired to the box and sticks right into the line? I would appreciate any info you guys can send my way.
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