Circuit Description

While engine is being cranked, battery voltage is applied to ECM terminal STA. Signal is mainly used to increase fuel injection volume for starting injection control and after-start injection control. DTC is set when ECM does not receive starter signal. Possible causes are:

Starter signal open or short circuit.
Ignition switch or starter relay open or short circuit.
ECM.

NOTE: Scan tester diagnosis can only be attempted with Toyota scan tester operated in CHECK mode.