1995 International 9200 A/C relay Problem

Discussion in 'International Forum' started by springtown76, Sep 13, 2019.

  1. springtown76

    springtown76 Bobtail Member

    12
    5
    Mar 1, 2019
    0
    BackGround. 1995 International 9200 12.7L Series 60 Detroit
    The air conditioning system worked fine late last summer hauling forage until it blew the belt. Long story short, that truck doesn't get used much, and its finally in the shop getting attention. I put on the new belt and tensioner, idler pulley and went to fire up the a/c, compressor wouldn't kick in. Check the usuals, switch under the passenger seat gets power to both sides, fuse was good, relay clicks when the switch in the dash comes on, but no power out to the compressor. Ended up screwing around with the a/c relay, and noticed when I pushed it back in, for a slight moment, I had power to the compressor, and then that fast it was gone. Now if I hold the relay just slightly at an angle, it will put power to the compressor, and then when I push it all the way in, it kills power to the compressor. I know I must be missing something completely obvious, but searching for some help. Thanks in advance
     
  2. Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.

  3. Heavyd

    Heavyd Road Train Member

    7,626
    6,027
    Feb 4, 2009
    0
    Try swapping another relay to see if the problem follows the relay or you have a bad socket. The terminals inside get sloppy and have a poor fit and poor electrical contact. Look closely at the plastic to see if there is any signs of melting which is due from a bad connection.
     
    springtown76 Thanks this.
  4. springtown76

    springtown76 Bobtail Member

    12
    5
    Mar 1, 2019
    0
    Swapped relays around, get the same thing to happen. There isn't any melted plastic around where the relay plugs in, but I can just get my finger wiggled back there and just touch the wires. The terminals inside the socket seem to move around fairly easy. I'll maybe start there. I'll post an update as I get through that.
     
  5. springtown76

    springtown76 Bobtail Member

    12
    5
    Mar 1, 2019
    0
    Also, just did some looking on here again. No melted plastic, relay is fine, terminals are actually fine on the back of the socket, not loose and the relay fits on tight. The next question would be, looking at the socket from the passenger seat, do you know which terminals do what? I assume the left terminal is ground, middle terminal is power out to compressor. Just not sure on the right and bottom. As soon as you throw the ac switch on theres power to the top, right, and bottom. If you move the relay in such a way you take power away from the top, then you instantly get power down to the compressor.
     

    Attached Files:

  6. Heavyd

    Heavyd Road Train Member

    7,626
    6,027
    Feb 4, 2009
    0
    Check the relay numbers on the body. Pin 30 is usually main power in, 87 is that main power back out when the relay is triggered. Pin 85 is where the signal power comes in to trigger the relay, and 86 would be ground. One of those terminals must be loose and making a bad connection if you can wiggle it to fix it. It will still fit tight when only 2 of 4 terminals are in good shape.
     
    AModelCat Thanks this.
  • Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.