With 4L60 Transmission

DTC 73 Pressure Control Solenoid (PCS) Circuit (Current Error):

Pressure Control Solenoid (PCS) Circuit:

CIRCUIT DESCRIPTION
The pressure control solenoid is a Powertrain Control Module (PCM) controlled device used to regulate transmission line pressure. The PCM compares Throttle Position Sensor (TPS) voltage, engine RPM and other inputs to determine the line pressure appropriate for a given load. The PCM will regulate the pressure by applying a varying amperage to the pressure control solenoid. The applied amperage can vary from 0.1 to 1.1 amp. The PCM then monitors the amperage at the return line.

DTC 73 WILL SET WHEN
^ No DTC 75 stored.
^ The return amperage varies greater than 0.16 amp from the commanded amperage.
^ All conditions are met for at least one second.

ACTION TAKEN (PCM will default to)
Maximum line pressure.

DTC 73 WILL CLEAR WHEN
The fault condition(s) no longer exist, and the ignition switch is cycled "OFF" then "ON."

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks the ability of the PCM to command the pressure control solenoid.
2. This test checks internal transmission harness and the pressure control solenoid for incorrect resistance.

DIAGNOSTIC AIDS
Check for poor connections at PCM and at transmission connector.