Starter Signal Circuit

1AR-FE ENGINE CONTROL: SFI SYSTEM: Starter Signal Circuit
- Starter Signal Circuit

DESCRIPTION

While the engine is being cranked, current flows from terminal ST1 of the ignition switch to the park/neutral position switch and also flows to terminal STA of the ECM (STA Signal).

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. CHECK WHETHER ENGINE STARTS

(a) Check if the engine can be cranked.

Result





B -- READ VALUE USING TECHSTREAM (STARTER SIGNAL)
A -- Continue to next step.

2. READ VALUE USING TECHSTREAM (STARTER SIGNAL)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Data List / Starter Signal.

(e) Read the value displayed on the Techstream when the ignition switch is turned to ON and the engine is started.

OK:





Result





B -- CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH -ST RELAY - ECM)
A -- Continue to next step.

3. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY

(a) Inspect the park/neutral position switch assembly Component Tests and General Diagnostics.

NG -- REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Removal
OK -- Continue to next step.

4. INSPECT IGNITION SWITCH

(a) Inspect the ignition switch Testing and Inspection.

NG -- REPLACE IGNITION SWITCH Removal
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - PARK/NEUTRAL POSITION SWITCH - ECM)

(a) Disconnect the ignition switch connector.

(b) Disconnect the park/neutral position switch assembly connector.

(c) Disconnect the ECM connector.

(d) Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):





Standard Resistance (Check for Short):





(e) Reconnect the ECM connector.

(f) Reconnect the ignition switch connector.

(g) Reconnect the park/neutral position switch assembly connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

6. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH -ST RELAY - ECM)

(a) Remove the ST relay from the engine room relay block.

(b) Disconnect the park/neutral position switch assembly connector.

(c) Disconnect the ECM connector.

(d) Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):





Standard Resistance (Check for Short):





(e) Reconnect the park/neutral position switch assembly connector.

(f) Reconnect the ECM connector.

(g) Reinstall the ST relay.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures

7. READ VALUE USING TECHSTREAM (STARTER SIGNAL)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Data List / Starter Signal.

(e) Read the value displayed on the Techstream when the ignition switch is turned to ON and the engine is started.

OK:





NG -- CHECK HARNESS AND CONNECTOR (ECM - ST RELAY)

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures

8. CHECK HARNESS AND CONNECTOR (ECM - ST RELAY)

(a) Remove the ST relay from the engine room relay block.

(b) Disconnect the ECM connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):





(d) Reconnect the ECM connector.

(e) Reinstall the ST relay.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ECM Removal