1989 Ford Bronco II 4WD, Standard, M5OD-R1FACTORY OEM SERVICE PROCEDURE

TFI-IV Module: Notes

Remove distributor. Remove TFI module from distributor. Measure resistance between TFI-IV module terminals with ohmmeter. See Fig 1 and TFI-IV MODULE RESISTANCE table. If resistance is NOT as specified, replace TFI-IV module.

TFI-IV MODULE RESISTANCE

Between Terminals Resistance (ohms)
GND & PIP-IN Greater Than 500
PIP PWR & PIP-IN Less Than 2000
PIP PWR & TFI PWR Less Than 200
GND & IGN GND Less Than 2
PIP-IN & PIP Less Than 200
Fig 1: Identifying TFI-IV Module Terminals
G90H14321Courtesy of FORD MOTOR CO.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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