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Electronically Controlled Transmission Communication Circuit

CIRCUIT DESCRIPTION
When the vehicle is driven uphill under the cruise control, a signal to prevent a upshift until the end of the uphill slope is sent from the cruise control ECU to the electronically controlled transmission, in order to reduce shifting due to ON/OFF overdrive operation and to provide smooth driving when a downshifting in the electronically controlled transmission occurs.

Terminal ECT of the cruise control ECU detects a shift change signal (input to electronically controlled transmission No.2 solenoid) from the ECM.

When the vehicle speeds down and when terminal ECT of the cruise control ECU receives a downshifting signal, it sends a signal from terminal OD to the ECM to cut overdrive until the end of the uphill slope, and the gear shiftings are reduced and gear shifting points in the electronically controlled transmission are changed.

Wiring Diagram:






Steps 1 - 2:




steps 3 - 5:




INSPECTION PROCEDURE