Code 28, Trans. Range Pressure Switch: Notes

Transaxle range switch is a multiple signal switch that sends gear selector position information to the PCM. PCM determines gear selection from an internal table. This is important to maintain idle quality when shifting from Park to Drive as well as maintaining correct TCC engagement points. When Code 28 sets, PCM will default to 3rd gear until a correct signal is received by PCM.

NOTE: Test numbers refer to numbers on diagnostic chart.

& 2) These steps check for proper operation of transmission range switch.
This test checks for an open circuit, grounded circuit or short to voltage.