Default Desensitization

As of April 1996, a new TCM calibration has been released for all vehicles built starting in mid-February and is being made available to flash update previous 1996 model year 42LE. The 1997 and 1999 Prowlers already use this new software, no updates are needed. This new calibration reduces the tendency of the transmission to go into limp-in mode (2nd gear only in OD, 3, L, PRN03L positions) for the following intermittent conditions.

- P1768 Relay output always off
- P1782 2-4 pressure switch sense circuit
- P0736 Gear ratio error in reverse
- P0731 Gear ratio error in 1st
- P0732 Gear ratio error in 2nd
- P0733 Gear ratio error in 3rd
- P0734 Gear ratio error in 4th
- P0715 Input speed sensor error
- P0720 Output speed sensor error
- P1794 Speed sensor ground error

Previous calibrations resulted in an immediate limp-in mode condition when a DTC is sensed during Key ON, and the vehicle speed is below 45 mph.

The new calibration always sets at DTC as soon as an electrical, mechanical or hydraulic problem is identified. But the transaxle may not go into limp-in mode until the problem happens several times in a given key start or after several key starts while identifying the DTC in Park or Neutral before vehicle operation begins. In addition this new calibration will eliminate DTC's 23, 25, 26, and 27 which would have been set when trouble with two or three of the pressure switch circuits existed. The new calibration will set a single DTC for every affected pressure switch circuit instead of one combined code.