2nd Gen Non-Engine/Transmission A/C not working

[Bhale]

I've got no A/C in the truck. Can't find a blown fuse. I just replaced the A/C clutch relay in the PCM but no joy.



Ideas???



Thanks



Brian

 

[YEEHAW]

Is the clutch engaging? Were you using the A/C and it quit or is it the first time you turned it on this year?



Maybe you have a leak and low pressure won't let the clutch engage.

 

[Bhale]

Nope, no clutch engagement which is what prompted me to replace the relay.



Can't say when it stopped working. I always use it for defrosting the windshield but can't determine when it stopped...



I did give a jump start about 3 weeks ago ... ... ...

 

[YEEHAW]

Try jumping the clutch with the engine off to see if it engages. If it works, then, in my experience, you don't have enough refer in the system for the compressor to run. There should also be a pressure sender on the back of the compressor. Try disconnecting it.



All of the problems I've ever had with A/C units was due to leakage.

 

[jgallentine]

On my 99, the pressure switch is on the accumulator back by the firewall. If you unhook the plug and jump the two wires and the clutch engages, you are low on freon as the other post said.



I am in that boat as my evaporator is leaking. All the new parts are sitting in the garage along with guages and an Edge box just waiting for time.



Good luck.

 

[Forrest Nearing]

just had this happen to me on the way home from OK... turn on the AC and notice it's not cold... when I stopped for fuel, I hit the schrader valve on the line and had pressure... and when I turned the switch to AC, the compressor didn't click... generally, even if the pressure is on the low side, the compressor will at least click even if it disengages right after that.



came home, did a search on TDR and learned that the problem might be in the PCM... I found the two wires, unplugged the connector to the PCM, jumpered the pins, and turned the knob to AC... "CLICK"!



so I clipped the two wires, twisted them together, soldered the connection, wrapped with with electrical tape, and plugged the connector back into the PCM.



Forrest

 

[Bhale]

Forrest

Thanks for the reply! Can you point me to the correct wires to splice together? I'm not haveing much luck finding them... .



Brian

 

[MACHINEST]

Bhale

The best way to do it is to pull the ,2 wire plug,that plugs into the low pressure switch ,on the black round tank,(Dryer)back by the fire wall ,passanger side,pull the plug off and take a jumper wire and jumper across the plug,if your clutch kicks in, your low on feon,if so charge it ,don't run it with the jumper wire in it,if your low on feon (134A) You will burn up your compressor, Big bucks,The high side should read 215 lbs pressure at 80 dgrees out side,your center vent shoul be around 15-25 degrees when fully charged ,Hope this helps!

 

[DavidC]

Originally posted by MACHINEST

Bhale

your center vent shoul be around 15-25 degrees when fully charged ,Hope this helps!

BRRRRRRRRRRRR. I think you mean 15-25 less than the 80 outside.



Dave

 

[MACHINEST]

Davidc

I did a little test on my regular cab CTD,Year 2001. 5,It was in the metal building,with a Ashcroft 0-220 Deg Thermo laying on the seat,,I put the thermo on the center AC vent ,,, Fired her up! And pulled her out in the sun!

At 6:45 Hot sunny evening it was 90 degrees

Fired truck up 1200 RPM <AC Blower on high

At 6:47 Thermo read 48 degrees

At 6:49 Thermo read 40 degrees

At 6:59 EST it read 38 degrees

4-5 min total a drop in temp 52 degrees ,But i just charged it yesterday!

If there right they will cool!