Starter Signal Circuit

CIRCUIT DESCRIPTION
When the engine is cranked, the intake air flow is slow, so fuel vaporization is poor. A rich mixture is therefore necessary in order to achieve good startability. While the engine is being cranked, the battery positive voltage is applied to terminal STA of the ECM. The starter signal is mainly used to increase the fuel injection volume for the starting injection control and after-start injection control.

Wiring Diagram:

INSPECTION PROCEDURE

HINT: This diagnostic chart is based on the premise that the engine is cranked normally. If the engine is not cranked, proceed to the problem symptoms table (See Diagnosis by Symptom).

Steps 1 - 2:

TOYOTA hand-held tester

Steps 1 - 2:

OBD II scan tool (excluding TOYOTA hand-held tester)