Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Fuel pump control circuit / Circuit description
Toyota Corolla (E120): 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 coil of the circuit opening relay, the relay switches on, power is supplied to the fuel pump and the fuel pump operates.
While the ne signal is generated (engine running), the ecm keeps tr on (circuit opening relay on) and the fuel pump also keeps operating.
Wiring diagram
Other materials:
Circuit description
The p/t squib (lh) circuit consists of the airbag sensor assy center and seat
belt pretensioner (lh).
It causes the srs to deploy when the srs deployment conditions are satisfied.
Dtc b0135/73 is recorded when a short is detected in the p/t squib (lh) circuit.
Wiring diagram
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Vehicle control system
Ignition or starter switch assy
Replacement
1. Remove steering column cover
2. Remove ignition or starter switch assy
Disconnect the ignition switch connector and unlock
warning switch connector.
remove the 2 clamps.
remove the 2 screws and ignition switch.
Inspectio ...
Dtc check/clear
1. Dtc check (normal mode)
Notice:
hand–held tester only:
when the diagnostic system is switched from the normal
mode to the check mode, all the dtcs and freeze frame
data recorded in the normal mode will be erased. So before
switching modes, always check the dtcs and freeze frame
data, and ...