Cranking Holding Function Circuit
2UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: Cranking Holding Function Circuit
Cranking Holding Function Circuit
DESCRIPTION
The starter is controlled by the ECM. When the ECM detects a start signal (STSW) from the ignition switch, this system monitors the engine speed (NE) and continues to operate the starter until it has determined that the engine has started (engine speed reaches approximately 500 rpm). If the engine is already running and the ignition switch is turned to START, the ECM will not operate the starter.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
1. CHECK OPERATION OF ENGINE CRANKING
(a) When turning the ignition switch to the START position check if the starter motor starts.
OK -- CHECK FOR INTERMITTENT PROBLEMS
NG -- Continue to next step.
2. READ VALUE USING TECHSTREAM (STA SIGNAL)
(a) Connect the Techstream to the DLC3.
(b) Enter the following menu: Powertrain / Engine and ECT / Data List / Starter Signal.
(c) Confirm the starter signal status when the ignition switch is operated.
OK:
OK -- INSPECT STARTER RELAY
NG -- Continue to next step.
3. INSPECT ECM (STA AND STSW VOLTAGE)
(a) Measure the voltage of the E6 ECM connector while cranking the engine (ignition switch is in the START position).
Standard voltage:
Result:
C -- INSPECT IGNITION SWITCH ASSEMBLY
B -- REPLACE ECM
A -- Continue to next step.
4. INSPECT PARK / NEUTRAL POSITION SWITCH
(a) Disconnect the P1 park / neutral position switch connector.
(b) Measure the resistance between each terminal shown below when the shift lever is moved to each position.
Standard resistance:
(c) Reconnect the park / neutral position switch connector.
NG -- REPLACE PARK / NEUTRAL POSITION SWITCH
OK -- CHECK AND REPAIR HARNESS OR CONNECTOR (PARK / NEUTRAL POSITION SWITCH - ECM)
5. INSPECT STARTER RELAY
(a) Remove the starter relay (STA) from the engine room relay block.
(b) Measure the resistance of the starter relay.
Standard resistance:
(c) Reinstall the starter relay.
NG -- REPLACE STARTER RELAY
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (PARK / NEUTRAL POSITION SWITCH - STARTER RELAY, STARTER RELAY - BODY GROUND)
(a) Check the harness and the connector between the park / neutral position switch connector and the starter relay.
(1) Disconnect the P1 park/neutral position switch connector.
(2) Remove the starter relay from the engine room relay block.
(3) Measure the resistance between the wire harness side connectors.
Standard resistance (Check for open):
Standard resistance (Check for short):
(4) Reinstall the starter relay.
(5) Reconnect the park/neutral position switch.
(b) Check the harness and the connector between the starter relay and the body ground.
(1) Remove the starter relay from the engine room relay block.
(2) Measure the resistance between the starter relay and the body ground.
Standard resistance (Check for open):
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
7. INSPECT ENGINE ROOM RELAY BLOCK (STARTER RELAY VOLTAGE)
(a) Remove the Starter relay from the engine room relay block.
(b) Measure the voltage of the engine room relay block and body ground.
Standard voltage:
(c) Reinstall the Starter relay.
NG -- CHECK AND REPAIR HARNESS AND CONNECTOR (STARTER RELAY - BATTERY)
OK -- Continue to next step.
8. INSPECT STARTER ASSEMBLY
(a) Inspect the starter assembly Testing and Inspection.
NG -- REPAIR OR REPLACE STARTER ASSEMBLY
OK -- CHECK AND REPAIR HARNESS OR CONNECTOR (STARTER RELAY - STARTER, STARTER - BATTERY)
9. INSPECT IGNITION SWITCH ASSEMBLY
(a) Remove the lower finish panel.
(b) Disconnect the I18 ignition switch connector.
(c) Measure the resistance of the connector terminals shown in the chart below.
Standard resistance:
(d) Reconnect the I18 ignition switch connector.
NG -- REPLACE IGNITION SWITCH ASSEMBLY
OK -- CHECK AND REPAIR HARNESS OR CONNECTOR (ECM - IGNITION SWITCH, IGNITION SWITCH - BATTERY)