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:
Body
On–vehicle inspection
1. Canada:
tighten bolts and nuts on chassis and body
tighten the bolts and nuts on the chassis parts listed below, if
necessary
Front axle and suspension
drive train
rear axle and suspension
brake system
engine mounting
other chassis parts
...
Problem symptoms table
Hint:
use the table below to help determine the cause of the problem. The numbers
indicate the priority of the
likely cause of the problem. Check each part in order. If necessary, replace
these parts.
1. Headlamp and tail lamp
2. Front fog lamp system
3. Turn signal and hazard warni ...
Replacement
Hint:
installation is according to the reverse order of the removal.
1. Remove fr wiper arm rh
2. Remove fr wiper arm lh
3. Remove hood to cowl top seal
4. Remove cowl top ventilator louver lh
5. Remove cowl top ventilator louver rh
6. Remove front door weatherstrip rh
7. Remove front ...


