Toyota Corolla (E120): System description
The ecm uses signals from the vehicle speed sensor and crankshaft position sensor to detect the actual gear position (1st, 2nd, 3rd or o/d gear).
Then the ecm compares the actual gear with the shift schedule in the ecm memory to detect the mechanical trouble of the shift solenoid valves, the valve body or automatic transaxle (clutch, brake or gear etc.).

Monitor description
The ecm commands gear shifts by turning the shift solenoid valves ”on/off”. According to the input shaft revolution, intermediate (counter) shaft revolution and output shaft revolution, the ecm detects the actual gear position (1st, 2nd, 3rd or o/d gear position). When the gear position commanded by the ecm and the actual gear position are not same, the ecm illuminates the mil.
Monitor strategy

Typical enabling conditions





Typical malfunction thresholds



Typical malfunction thresholds



Other materials:
Do-it-yourself service precautions
If you perform maintenance
by yourself, be sure to follow
the correct procedure
as given in these sections.
Maintenance
WARNING
The engine compartment contains
many mechanisms and fluids that
may move suddenly, become hot,
or become electrically energized.
To avoid death or serious injury,
obser ...
Adjustment
1. Inspect shift lever position
When shifting the shift lever to each position, make sure
that it moves smoothly, and the position indicator displays
correctly.
Positions which can be shifted without pressing the
shift lever knob button
r " n " d, l " 2 " d &quo ...
Inspection procedure
1 Check security indicator light
Remove the security indicator.
check the indicator light, as shown in the illustration and
table.
Standard:
2 Check wire harness (tvip ecu security indicator)
Disconnect the tvip ecu and security indicator connectors.
  ...


