Circuit Description:
The PRNDL switch is mounted on the transaxle assembly. It is a multi-signal switch sending information relative to gear selector position to the PCM. The PRNDL assembly also contains the neutral safety (start) switch. The PRNDL switch uses four discreet circuits to pull four PCM voltages low in various combinations to indicate each gear range. The voltage level of each of the circuits is represented as Lo= Grounded HI= Open Circuit. The four digits displayed represent decoder A, B, C and Parity inputs in sequence.
CODE EO31 SETS WHEN
- Ignition is ON and Engine is OFF
- Vehicle speed is 0 MPH
- PRNDL indicates a gear other than park or neutral
- All conditions met for .13 seconds for 3 consecutive startups OR
- The PRNDL status indicators (A,B,C,P) indicate a incorrect combination of LO and HI for more than 10 seconds.