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 park/neutral position switch detects the shift lever position and sends
signals to the ecm.
Monitor description
The park/neutral position switch detects the gearshift position and sends a
signal to the ecm.
For security, the park/neutral position switch detects the gearshift positio ...
Inspection procedure
Hint
Advanced timing over
(valve timing is out of specified range)
P0011
Retarded timing over
(valve timing is out of specified range)
P0012
If dtc p0011 or p0012 is displayed, check the vvt system circuit.
Read freeze frame data using the hand–held tester o ...
Circuit description
The shift solenoid valve sl is turned ”on” and ”off” by signals from the ecm
in order to control the hydraulic
pressure operation, the lock–up relay valve, which then the controls operation
of the lock–up clutch.
Fail safe function:
if the ecm detects a malfunction, it turns the ...


