A/C Clutch Power Issue
#1
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A/C Clutch Power Issue
I've got a 1995 SC300 and have had an issue with the car since I first got in a year and a half ago and finally feel like chasing the problem. Anyways, my clutch on the ac compressor does not get power to engage.
I ran the diagnostics on it and came back with code 12 Ambient Temp Sensor, I did more research and found that on max cold it should not matter if the sensor is working or not, I looked for the sensor and found that it is missing along with the connector is cut for it.
I checked the pressure in the system and it is good, then ran a 12v positive to the wire that engages the clutch when I do so the air blows ice cold. The A/C light on the hvac controls stays lit up but never any engagement of the clutch or power coming to it.
Tried to swap the relay with the starter relay still no luck. Could the ambient sensor not being there leave an open circuit causing this issue? I tried to find a wiring diagram for the HVAC components with no luck.
Any ideas are greatly appreciated as Alabama summers are coming soon and I would like to drive the car some this summer.
I ran the diagnostics on it and came back with code 12 Ambient Temp Sensor, I did more research and found that on max cold it should not matter if the sensor is working or not, I looked for the sensor and found that it is missing along with the connector is cut for it.
I checked the pressure in the system and it is good, then ran a 12v positive to the wire that engages the clutch when I do so the air blows ice cold. The A/C light on the hvac controls stays lit up but never any engagement of the clutch or power coming to it.
Tried to swap the relay with the starter relay still no luck. Could the ambient sensor not being there leave an open circuit causing this issue? I tried to find a wiring diagram for the HVAC components with no luck.
Any ideas are greatly appreciated as Alabama summers are coming soon and I would like to drive the car some this summer.
#2
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diagram 26 / 26b on this page of the following thread
https://www.clublexus.com/forums/per...de-easy-6.html
you will find your AC / HVAC electrical diagrams
https://www.clublexus.com/forums/per...de-easy-6.html
you will find your AC / HVAC electrical diagrams
#4
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Checking some more I have power on pin 5 and pin 2 on the relay for the A/C. Am I supposed to have power on pin 2 that comes from the ecu or should it be a ground?
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