Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Electronic controlled automatic transaxle / Shift solenoid ”a” control circuit
low/high
Toyota Corolla (E120): Shift solenoid ”a” control circuit low/high
Dtc p0973 shift solenoid ”a” control circuit low (shift solenoid valve s1)
Dtc p0974 shift solenoid ”a” control circuit high (shift solenoid valve s1)
Other materials:
Circuit description
The variable valve timing (vvt) system includes the ecm, the oil control
valve (ocv) and the vvt controller.
The ecm sends a target ”duty–cycle” control signal to the ocv. This control
signal, applied to the ocv,
regulates the oil pressure supplied to the vvt controller. Camshaft timin ...
Inspection procedure
1 Check side squib(rh) circuit(airbag sensor assy center – front
seat airbag assy rh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the front seat airbag assy ...
Monitor description
The battery supplies electricity to the ecm even when the ignition switch is
off. This electricity allows the
ecm store data such as dtc history, freeze frame data, fuel trim values, and
other data. If the battery voltage
falls below a minimum level, the ecm will conclude that there is a fault ...


