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How To Use LOGICON Checker

  1. Set each switch of checker to off position.
  2. Connect red wire to positive terminal of battery. Connect Black wire to negative terminal of battery.
  3. Securely connect each connector of mode control switch to the White connectors of checker.
  4. Set power switch (SW1) to the "ON" position. At this time the Red LEDs Nos. 1, 3, 6 and 8 will illuminate when the REC-FRESH switch and that A/C switch are turned off. If one of the Logical Control switches are turned on, the Green LED corresponding to that switch will illuminate.
  5. Press the control switches in order and check whether or not the corresponding Green LED on the checker illuminates. If the LED does not illuminate, the problem is in the Logical Control switch.
    NOTE: The Red No. 1 LED will go off when the REC-FRESH switch is turned on while using the checker, but this is a normal function. When the HEAT/DEF button is pushed on, the No. 4 LED comes on. This indicates correct operation.
  6. Operate SW 3, SW 4, and SW 5 of checker and perform the following checks:
    • Check whether or not LED No. 2 illuminates and LED No. 3 goes off when SW 3 lever is moved to the "ON" position.
    • Check whether or not LED No. 5 illuminates and LED No. 6 goes off when SW 4 lever is moved to the "ON" position.
    • Check whether or not LED No. 7 illuminates and LED No. 8 goes off when SW 5 lever is moved to the "ON" position.
  7. Set the illumination switch to "ON". Check the indicator lights of the Logical Control buttons. Perform the test described in step 5) and check to see if the indicator light of each Logical Control button is in the dimmed mode. If not, the problem is in the Logical Control switch.
Fig 1: Logicon Switch
G66131
Fig 2: Checking Rec/Fresh Select Circuit
G66134
Fig 3: Checking Air Mix Control Circuit
G66138
Fig 4: Checking Illumination Circuit
G66140