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Force Motor Circuit Check: Notes

NOTE: This flow chart requires the use of a bidirectional (Tech 1) Scan tester.

The force motor is a PCM/TCM-controlled device used to regulate transmission line pressure. The PCM/TCM looks at TPS voltage, engine RPM, and other inputs to determine the appropriate line pressure for a given load, then regulates the pressure by applying a variable amperage to the force motor. The applied amperage varies from .1-1.1 amps.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. This test verifies an amperage difference of .16 amp or more, and tests the PCM/TCM's ability to control amperage to the force motor.
  2. This test checks the force motor for internal shorts.
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