air conditioning ecu trigger

  • Rick88ss
    Rick88ss
    Senior Member
    • 2433

    air conditioning ecu trigger

    I'm thinking about running a Z32 ecu in my Z with Nistune. The Z32 has a wire input from the A/C controls and a wire output to turn on the compressor and activate the FICD. Since it has an input from the A/C now the Z32 ecu adjusts the AAC idle valve accordingly to maintain a steady idle along with extra fuel and timing changes.
    Question is how is this controlled on the 1988 Turbo Z31 ecu? What wire let's the ecu know that the a/c has been turned on so the ecu can control the AAC idle valve on the Z31?
    Shiro #443

  • Augustus Maximus
    Augustus Maximus
    Senior Member
    • 1739

    #2
    Pin 22 seems to be the one.
    Cha iro

    enjoy building it yourself.
    if it fails, fuck it.
    at least you gave it a whirl.
  • Rick88ss
    Rick88ss
    Senior Member
    • 2433

    #3
    I was looking at the FSM last night and saw that. When the compressor relay is activated the Y/G wire from the relay feeds 12V to pin 22 into the ecu and the same wire also provides power to the FICD and the magnetic clutch on the a/c compressor.
    The Z32 ecu is different because the wire that goes to pin 46 is the one that tells the ecu that the a/c has been switched on. But the wire comes from the thermo control amp (thermo switch in the Z31). In the z31 it's the wire that activates the compressor relay. It's the Y/L wire that goes to the low pressure switch then out of the other side of the low pressure switch as a Y/R wire , then to the compressor relay.
    So then pin 9 of the Z32 ecu activates the compressor relay and pin 33 activates the FICD.

    I'm pretty sure I have it figured out now. It took awhile comparing the Z31 and Z32 wiring diagrams.
    I'm gonna start the installation of the Z32 ecu with NISTUNE into my Z31 soon.
    Shiro #443

  • les_joey_paul
    les_joey_paul
    Senior Member
    • 743

    #4
    Interested in this.
    Are you gonna use z32 coil packs ? and engine harness?
    http://z31performance.com/showthread…2-2-(-now-NA2T
    My build thread (:
  • Rick88ss
    Rick88ss
    Senior Member
    • 2433

    #5
    I'm gonna use LS2 Yukon coils and a modified Z32 harness and Z32 MAF
    Shiro #443