Diagnostic Aids

If the A/T shift lock control circuit is shorted to ground, the automatic transmission shift lock control solenoid will be inoperative. The shift lever will not shift out of PARK position with the brake pedal depressed.
Perform the tests while wiggling the wires and connectors. This may often cause an intermittent malfunction to appear. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.