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Wiring Harness Check

  1. Disconnect ignition module connector from ignition module. Disconnect wire at "S" terminal of starter relay. Attach negative lead of voltmeter to distributor base and measure battery voltage at battery. With negative lead of voltmeter still connected to distributor base, check voltage in each of the following situations:
    • Positive voltmeter lead connected to terminal No. 1 (TFI-I only) or terminal No. 2 (TFI-IV only) of ignition module connector with ignition switch in "RUN" position. See Fig 1 and Fig 2 .
    • Positive voltmeter lead connected to terminal No. 2 (TFI-I only) or terminal No. 3 (TFI-IV only) of ignition module connector with ignition switch in "RUN" position. See Fig 1 and Fig 2 .
    • Positive voltmeter lead connected to terminal No. 3 (TFI-I only) or terminal No. 4 (TFI-IV only) of ignition module connector with ignition switch in "START" position. See Fig 1 and Fig 2 .
      Fig 1: Test Points for Wiring Harness Check Applicable to TFI-I models only.
      G3451
  2. If reading was at least 90 percent of battery voltage, proceed to PICK-UP & IGNITION MODULE CHECK (TFI-I engines) or to EEC SPARK SIGNAL WIRE CONTINUITY CHECK (TFI-IV engines). If reading was less than 90 percent of battery voltage, inspect for wiring harness problems or a worn or damaged ignition switch.
Fig 2: Test points for Wiring Harness Check Applicable to TFI-IV models only.
G3452