A/T - Improper 4-3 and 3-4 Shifts
TECHNICAL BULLETIN # 315DATE 1995
TRANSMISSION: 41TE (A604)/42LE
SUBJECT: Improper 4/3-3/4 shifts
APPLICATION: Chrysler
41TE (A604)/42LE
Improper 4/3-3/4 Shifts
The newest generation of replacement transmission controllers can cause improper 4/3-3/4 automatic shifts in certain models.
Certain 989 through 1992 AA body vehicles, (LeBaron without a Body Control Module, Spirit and Acclaim) have a wire at TCM pin location number 49. This wire is used to monitor brake switch operation. The new generation of controllers for these applications does not use this signal.
The pin function of the new controllers has been designed for a fourth gear cancel mode.
Using the new design controller on the before mentioned vehicles, will cause the transaxle to shift from fourth to third when the brake pedal is pressed. Pressing the brake pedal again (at the proper speed) will cause the unit to shift back to fourth gear again.
To avoid this problem (when updating to the new TCM), locate pin number 49 at the TCM connector (figure 1). Cut the wire approximately three inches away from the TCM. Fold the ends over and seal them with a couple of pieces of shrink tubing. The modification is now complete.