Toyota Celica 2005 Repair Manual page 483

DI−284
Fuel Pump Control Circuit
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.
EFI
Ignition Switch
AM2
Battery
2005 CELICA (RM1131U)
DIAGNOSTICS
EFI Relay
ST2
From
Crankshaft Position Sensor
Clutch Start Switch*
Park/Neutral position Switch*
− ENGINE (1ZZ−FE)
C/OPN Relay
1
2
ST Relay
Starter
482
Fuel Pump
ECM
FC
Tr
NE
STA
1
* : M/T
2
* : A/T
DIC73−02
A21426