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
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 ...
Check dlc3
The vehicle’s ecm uses the iso 9141–2 for communication
protocol. The terminal arrangement of the dlc3 complies
with sae j1962 and matches the iso 9141–2 format.
Hint:
if the display shows unable to connect to vehicle
when you have connected the cable of the obd ii scan tool or
the h ...
For vehicles equipped with mobile communication system
Install an antenna as far as possible away from the ecu
and sensors of the vehicle’s electronic systems.
install an antenna feeder at least 20 cm (7.87 In.) Away
from the ecu and sensors of the vehicle’s electronic systems.
For details of the ecu and sensors locations, refer ...


