Pressure Control Solenoid Circuit Check: Notes
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Pressure control solenoid is a PCM-controlled device used to regulate transmission line pressure. PCM looks at TPS voltage, engine RPM, and other inputs to determine appropriate line pressure for a given load, then regulates pressure by applying a variable amperage to pressure control solenoid. Applied amperage varies from .1 to 1.1 amps.
PCM then monitors amperage at return line. If return amperage varies greater than .16 amp from commanded amperage for at least one second, Code 73 will set. When Code 73 sets, full line pressure will be applied, causing harsh shifts until next ignition cycle. Code will remain stored in memory, and pressure control solenoid will resume normal operation until conditions for code reoccur.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- This test checks ability of PCM to command pressure control solenoid.
- This test checks for voltage at PCM.
- This test checks internal transmission harness and pressure control solenoid for low resistance.
- This test checks internal transmission harness and pressure control solenoid for high resistance.