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:
Mechanical system tests
1. Perform mechanical system tests
Measure the stall speed.
The object of this test is to check the overall performance of the transaxle
and engine by measuring
the stall speeds in the d and r positions.
Notice:
Do the test at normal operating atf temperature 50 to 80 °c (122 to
...
Problem symptoms table
The suspected circuits or parts for each problem symptom are shown in the
table below. Use this table to
troubleshoot the problem when a normal code is displayed in the diagnostic
trouble code chart but the problem
is still occurring. Numbers in the table indicate the order in which the
circ ...
Removal & installation and disassembly & re
1. Remove bench type rear seat cushion assy (, 72–8)
2. Remove rear floor service hole cover
3. Work for preventing gasoline from spilling out
start the engine.
after the engine has stopped on the its own, turn the ignition
switch to lock.
4. Disconnect fuel tank main tu ...


