bypassed the ac pressure switch... Now on to the next step

oilspotoilspot Wagonist
in Electronics, Fueling & Air Conditioning
Ac doesn't work on my new 89'. My friend that does home ac heating /cooling told me I need to find out where the pressure switch is, and bypass it. Then see if the compressor will kick on. and then from there add r-134a and go from there. There's no pressure in the system, but he said it's good that it wasn't under a vacuum.

So where's the pressure switch?

Trying to figure out if I need a new compressor/ receiver drier before it's hot as hell.

Comments

  • bam-bambam-bam Council Member
    It's in the line from the condenser outlet to the evaporator inlet. Look at the lower/smaller of the 2 lines running fore-and -aft above the tranny. Way up front, almost at the radiator is a 2-prong switch.
  • oilspotoilspot Wagonist
    So I bridged the connection together. Nothing. The ac button doesn't light up, no noise, nothing.
    I figured that if the compressor was bad, that the button would still turn on, but there would be no activation of the clutch... or something like that.

    None of the fuses indicate that they go to the ac. I guess I'll just pull the middle console away and start testing to see if there's even power going to the switch.

    I would be nice if the manual covered anything about this. That little manual has proven to be a waste of money. It has not covered a single problem that I've had to work with.

    I don't know what I'm doing... help! :D
  • Eagle BeagleEagle Beagle familEE
    steps are, afaik :
    22 degrees, dont ask me why
    fanswitch/blower on

    the ac&indicatorlight is connected on that fanswitch
    position ground and numbered 6 is ac
  • oilspotoilspot Wagonist
    Eagle Beagle wrote:
    steps are, afaik :
    22 degrees, dont ask me why
    fanswitch/blower on

    the ac&indicatorlight is connected on that fanswitch
    position ground and numbered 6 is ac

    what?

    sorry, I really don't know anything about air conditioning. I'm not sure what to make of afaik : 22 degrees

    But I guess your saying that the ac fuse is in the number 6 fuse spot.
  • Eagle BeagleEagle Beagle familEE
    The ac button doesn't light up

    it was a telegram
    22 degrees celsius before the ac kicks in
    (and i did ask, dont ask : )

    your lightindicator of the ac is integrated with the fanswitch.
    that fanswitchconnector is numbered...
    so ground and number six makes your airco work and
    makes the ac indicator light glow when you push the ac-button
    check that line 1st, see quote above..





    hope this makes sense

    ps. not mentioning a fuse-position and/or spot
    have phun : D
  • oilspotoilspot Wagonist
    Eagle Beagle wrote:
    The ac button doesn't light up



    so ground and number six makes your airco work and
    makes the ac indicator light glow when you push the ac-button
    check that line 1st, see quote above..




    Ok... so #6 on the switch should be hot. and the button should take that to ground, complete the circut, and make the whole deal work?
  • Eagle BeagleEagle Beagle familEE
    Ok... so #6 on the switch should be hot. and the button should take that to ground, complete the circut, and make the whole deal work?
    and if your fanswitch is ON, your systempressure is OK, dryer/compressor is OK, all other parts of the system OK ?

    yeah, no problem
    : )
  • oilspotoilspot Wagonist
    Picked up a ac switch at the junkyard right by my house. Bypassed the pressure switch again, Added some r134a. And to my suprize....
    I've got A/C.

    I never though I would get it working so easily, or so cheaply.
    I love this car more every day!
  • awreckawreck Band Wagon
    Ok so Im sorry to bring back a dead thread but I am having the exact same prblem and I don't know how to solve it. I press the button and nothing. No light, no compressor clutch, idle stays the same. Nothing. I Am very confused as to where to start. And which relay is which? How do I bypass it. So many questions I know but I just need help.
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