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:
Inspection procedure
1 Inspect parking brake switch circuit
Check for open and short circuit in parking brake switch circuit
2 Inspect brake fluid level warning switch circuit
Check the brake fluid level in reservoir.
check for open and shot circuit in brake fluid level warning
switch circuit
...
Things you should know
■ If you notice any symptoms
If you notice any of the following symptoms, refer to the likely cause and the
solution, and re-check.
If the symptom is not resolved by the solution, have the vehicle inspected by
your Toyota dealer.
CAUTION
■When using the rear view monitor system ...
Inspection procedure
1 Inspect shift solenoid valve(s1)
Remove the shift solenoid valve s1.
measure the resistance according to the value(s) in the
table below.
Standard:
Connect the positive (+) battery lead to the solenoid connector
terminal, and the negative (–) battery lead to the
solenoid ...