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Chart:

Schematic:

DESCRIPTION
The PRND321 sensor, part of the gear selector switch, is mounted on the transaxle and operates as a potentiometer that sends gear selection information to the Body Control Module (BCM) as a variable voltage signal. The PRND321 signal, CKT 356, is calculated as a percent of available ignition voltage to gear selector position. Code B127 will set if the voltage signal is above or below the normal operating range, which could be the result of:
- CKT 139, 356 or 736 open or shorted to ground.
- Faulty gear selector switch or switch adjustment.
- Faulty BCM.
- Faulty terminal contacts of the gear selector switch, dash to engine harness interconnect or BCM.

TEST DESCRIPTION
The numbers below refer to circled numbers on the diagnostic chart:
1. Check BD41 to determine if PRND321 is within normal range of values.
2. A low BD41 value could be a misadjusted switch as well as an open or short to ground in CKT 139 or 356. Try adjusting switch before replacing.
3. Cycle the gear selector through all the gears, but disregard BD41 readings between gear selector positions. If a low reading is found at some particular position, try adjusting switch before replacing.
4. A high BD41 value indicates an open in the switch or CKT 736.