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:
Terminals of ecu
1. Inspect tvip ecu
Inspect the ecu–b, dome and ecu–ig fuses.
disconnect the tvip ecu connector, and the continuity and voltage of
check each terminal of the disconnected
connector.
Standard:
If the result is not as specified, the vehicle’s side may malfunction.
Reco ...
Circuit description
When a misfire occurs in the engine, hydrocarbons (hc) enter the exhaust in
high concentrations. If this hc
concentration is high enough, there could be an increase in exhaust emissions
levels. High concentrations
of hc passing through the catalyst also cause to temperature of the catalyst to ...
Circuit description
The crankshaft position sensor (ne signal) consists of a magnet, iron core
and pickup coil.
The ne signal plate (crankshaft position sensor plate) has 34 teeth and is
installed on the crankshaft. The
ne signal sensor generates 34 signals for each engine revolution. This sensor
monitors a p ...