Toyota Corolla (E120): Circuit description

Monitor description
The ecm commands gearshift by turning the shift solenoid valves ”on/off”. When there is an open or short circuit in any shift solenoid valve circuit, the ecm detects the problem and the mil comes on. Illuminating the mil, the ecm performs the fail–safe and turns the other shift solenoid valves in good condition ”on/off” (in case of an open or short circuit, the ecm stops sending current to the circuit.).
Monitor strategy

Typical enabling condition

Typical malfunction thresholds

Component operating range

Wiring diagram
Other materials:
Inspection procedure
Hint:
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 troubleshooting, it is
useful for determining whether
the vehicle was running or stopped, the engine was warmed up or not, th ...
How to proceed with troubleshooting
1 Vehicle brought in
2 Customer problem analysis check and symptom check
3 Problem symptoms table
Without applicable symptoms, proceed to ”a”
with applicable symptoms, proceed to ”b”
4 Perform troubleshooting in the following method, depending on
malfunction symptom ...
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 ...


