The A/C compressor won't kick on.

[patrick66]

When I turn ON the air conditioner, I get the fan, but the compressor clutch does not kick on. The fuse is good, as the other items on that same circuit all function properly. I do not get power at the compressor. I did run a hot wire from the compressor to the battery (+) and the compressor clutch kicks on like it is supposed to. So, I know the compressor works, and I know I am not getting power to the compressor when it is all plugged in normally. All of the other heat and vent functions, and the fan, all work as they are supposed to.

This is NOT Auto-Temp II!!!

I do not have a '78 FSM, so I'm a little bit stumped here.
Anyone have an idea what's up? It worked just fine last Summer, and would freeze you out. It was properly converted to R134 in 2006 by the PO, with a new drier & condensor.

 

[Big_John]

Most likely the charge is low.

Check the power at the pressure switch.

 

[1978 NYB]

Looks like you have to trace the compressor power wire back. It should follow along in the wiring harness on the right side valve cover. It should go into a white plastic junction box right behind the right side valve cover. I have removed a lot of Lean Burn wiring on my NYB and only have 2 wires left in that junction block. The A/C compressor power wire and the ignition power wire to the distributor.

 

[1978 NYB]

PM sent

 

[patrick66]

Yup, it was low on Freon by about two pounds. The air will freeze your nuts off now!

 

[rumpfox]

early models didn't have pres. switches whitch let you lockup the compressure when it got low on gas an burn up everything my 66 n.y and 68 imp. done it to my wife cause she didn't no what was happening