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
1 Check fuse(ecu–ig)
Remove the ecu–ig fuse from the instrument panel j/b.
check the continuity of the ecu–ig fuse.
Ok: continuity
2 Inspect terminal voltage(b)
Remove the cruise control ecu assy with connector still
connected.
turn the ignition switch ...
Speedometer sensor (atm)
Replacement
1. Remove air cleaner case
2. Remove air cleaner hose no.1
3. Remove speedometer sensor
disconnect the connector.
remove the bolt and speedometer sensor assembly.
remove the clip and driven gear from the speedometer
sensor.
4. Install speedometer sensor
...
Circuit description
In the diagram below, when the engine is cranked, current flows from terminal
st2 of the ignition switch to
the starter relay coil and also current flows to terminal sta of the ecm (sta
signal).
When the sta signal and ne signal are input to the ecm, tr is turned on, current
flows to the c ...


