Transmission Position Sensor/Switch: Testing and Inspection

Digital Transmission Range (TR) Sensor Diagnosis Chart

Digital Transmission Range (TR) Sensor Diagnosis Chart:

Wiggle Test Information for Open/Shorts
^ TR4, TR3A, TR2 and TR1 are all closed in PARK. PARK is a good position to check for intermittent open circuits (with scan tool monitoring TRD).
^ TR4, TR3A, TR2 and TR1 are all open in OVERDRIVE, so OVERDRIVE is a good position to check for shorts to ground. To determine the shorted components while observing TRD, unplug the TR and determine if the short goes away. If the short is still present unplug the transmission harness and determine if the short goes away. If the short is still present, then the short is in the PCM or vehicle harness. Remove the suspect circuit(s) wire terminal from the PCM connector. If the short is still present, then the PCM has an internal failure, otherwise the failure is in the vehicle harness.