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:
Components
...
Fail–safe chart
If any of the following codes is recorded, the ecm enters the fail–safe mode.
Check for intermittent problems
Hand–held tester only:
by putting the vehicle’s ecm in the check mode, the 1 trip detection logic is
possible instead of the
2 trip detection logic, and the sensitivity to de ...
Inspection procedure
Hint:
start the inspection from step 1 in case of using the hand–held tester and start
from step 2 in case of not
using the hand–held tester.
1 Read value of hand–held tester(front speed sensor)
Select the datalist mode on the hand–held tester.
check that there is no differe ...