Automotive Air Conditioning Information Forum (Archives)

peanutaxis on Fri February 19, 2016 5:44 AM

Year: 1995
Make: Toyota
Model: Corolla
Engine Size: 1600
Refrigerant Type: 134a

Just wondering why my compressor has 3 pins/wires instead of two? Anyone know what they do? I was just looking to jump my compressor to see if the clutch will engage. No gas in system and the clutch doesn't do anything when I turn the ac on.


thanks,
p

mk378 on Fri February 19, 2016 8:43 AM

Probably two wires for the rpm sensor and one for the clutch coil-- coil has internal ground.

Do not jump compressor with engine running. OK to do it with engine stopped, you should see and hear the clutch plate pull in to the pulley. Running with no refrigerant is bad, that is why it is designed to turn off.

peanutaxis on Fri February 19, 2016 5:35 PM

Quote
Originally posted by: mk378
Probably two wires for the rpm sensor and one for the clutch coil-- coil has internal ground.



Do not jump compressor with engine running. OK to do it with engine stopped, you should see and hear the clutch plate pull in to the pulley. Running with no refrigerant is bad, that is why it is designed to turn off.

Thanks heaps for your response.

Yeah I thought it might sense that there's no gas and not work.
A couple Qs. I assume that you mean that it also has an rpm sensor so that the clutch doesn't engage when the belt is not spinning?
The internal ground - would that still be common with the car body?


thanks