Transmission Control Systems: Description and Operation

Engine And Transaxle Total Control Signal Circuit:

There are 3 communication lines providing torque reduction request and torque reduction execution (retared timing) signals. They connect the engine ECU with the transaxle control unit. The units are both located under behind the center console. Two of these lines send 5 Volts from the engine ECU to the transaxle control unit. The other is 5 Volts from the transaxle control unit to the engine ECU.

Communication between control units is accomplished by switching ground circuits of the 5V reference signal "ON" or "OFF" as determined by the proper control unit for the driving conditions. This functions to provide better transaxle shifting and limits traction loss during acceleration.