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A/C On Switch System Test

  1. Turn ignition switch to RUN position. Move mode selector switch to OFF position. With A/C control assembly connector connected, measure voltage between mode selector switch Dark Green wire and ground. For wiring schematics, see mini-schematics in A/C CLUTCH under MISCELLANEOUS ECM CONTROLS  in this article.
  2. Battery voltage should be present. If battery voltage is present, mode selector switch is operating normally. If battery voltage is not present, check Dark Green wire from selector switch to fuse for an open circuit.
  3. Check voltage between mode selector Dark Green wire and ground. Voltage should not be present. If voltage was present, replace mode selector switch.