Toyota Corolla (E120): Circuit description
When driving uphill under cruise control, in order to reduce the number of shifting due to on–off overdrive operation and to provide smooth driving, when down shifting in the electronically controlled transmission occurs, a signal to prevent upshift until the end of the uphill slope is sent from the cruise control ecu assy to the electronically controlled transmission.
Terminal ect of the cruise control ecu assy detects the shift change signal (output to electronically controlled transmission no.2 Solenoid) from the ecm.
If the vehicle slows down, also when terminal ect of the cruise control ecu assy receives down shifting signal, it sends a signal from terminal od to ecm to cut overdrive until the end of the uphill slope, and the number of gear shifts are reduced and gear shift points in the electronically controlled transmission are changed.
Wiring diagram

Other materials:
Inspection procedure
Hint:
perform the troubleshooting of dtc p0335 first. If no trouble is
found, troubleshoot the engine mechanical
systems.
Read freeze frame data using the hand-held tester or the obd ii scan tool.
Freeze frame data records
the engine conditions when a malfunction is detected. When tr ...
Hydraulic test
1. Perform hydraulic test
Measure the line pressure.
Notice:
Do the test at normal operation atf temperature 50 to 80 °c (122 to
176 °f).
The line pressure test should always be carried out in pairs. One
technician should observe
the conditions of wheels or wheel stopper outsi ...
Diagnostic trouble code chart
Notice:
when removing the part, turn the ignition switch to off.
Hint:
using sst 09843–18040, it connect the terminal tc and cg of dlc3.
If any abnormality is not found when inspecting parts, inspect the ecu and
ground points for poor contact.
If a malfunction code is displayed during ...


