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Temperature Dial Calibration

Be sure to allow sufficient time for engine to warm up and for system to turn on before attempting calibration, then proceed as follows:

  1. Connect tester J-23678 into wiring harness and programmer. Place control selector at "ECONOMY". Place tester Manual-Automatic switch in "MANUAL" position. Place temperature dial Calibrator switch in "CAL" (calibrate) position. Note voltmeter reading on tester.
  2. Press Compare button and note voltmeter reading. With the Compare button pressed in, rotate the temperature dial (thumbwheel) until voltmeter reading is same as in Step  1 (button not pressed in).
  3. Control panel temperature dial should be set at the temperature dial setting on the tester panel ("75"). If temperature settings do not correspond, use a suitable holding tool (J-21530) to retain gear on left side of temperature dial while turning the dial to correct setting ("75"). If temperature dial cannot be calibrated using this procedure, it has malfunctioned.
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