Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Electronic controlled automatic transaxle / Shift solenoid ”a” performance
(shift solenoid valve s1)
Toyota Corolla (E120): Shift solenoid ”a” performance (shift solenoid valve s1)
Dtc p0751 shift solenoid ”a” performance (shift solenoid valve s1)
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

Other materials:
Circuit description
The rear heated oxygen sensor is used to monitor oxygen concentration in the
exhaust gas. For optimum
catalytic converter operation, the air fuel mixture must be maintained near the
ideal ”stoichiometric” ratio.
The heated oxygen sensor output voltage changes suddenly in the vicinity of ...
Inspection procedure
Hint:
hand–held tester only:
narrowing down the trouble area is possible by performing ”a/f control” active
test (heated oxygen
sensor or other trouble areas can be distinguished).
Perform active test using hand–held tester (a/f control).
Hint:
”a/f control” is the active te ...
On–vehicle inspection
1. Inspection throttle body idle speed control valve assy
Notice:
it is impossible to check the resister value and the operation
of isc valve by itself, because the isc valve
has an ic circuit inside it, which transforms the duty
signal from the ecm to the derive signal.
After check ...


