Code 28, Trans. Range Pressure Switch: Notes

Transmission range switch is part of Transmission Neutral Start Switch (TMNSS) mounted on transaxle assembly. Transmission range switch is a multi-signal switch that sends information, relative to gear selector position, to PCM. PRNDL input consists of 4 discrete circuits to pull 4 PCM voltages low in various combinations to indicate each gear range. Voltage level of each of the circuits is represented as low equals grounded circuit and high equals open circuit. The 4 states displayed represent decoder parity, "A", "B"and "C" respectively.

Code will set when the following conditions are present.

• Ignition is on and engine off.
• Vehicle speed is zero MPH.
• PRNDL inputs indicate a gear other than Park and Neutral.
• All conditions are met for .13 second for 3 consecutive start-ups.

or:

• PRNDL inputs status indicators ("P", "A", "B"and "C") indicate an incorrect combination of low and high for a minimum of 10 seconds. PCM will also command stepper motor cruise control to be inhibited.

Code will cause PCM to command a drive-4 shift position. Code does not illuminate the Malfunction Indicator Light (MIL).

1. Checks for proper operation of transmission range switch.
2. Checks for an open, grounded or shorted to voltage circuit.