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Cranking Holding Function Circuit

CRANKING HOLD FUNCTION CIRCUIT

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

Step 1:




Step 2 - 3:




Step 4 - 6:




Step 7 - 8:




Step 9:




Hand held tester:

Step 1 - 2:




Step 3 - 5:




Step 6 - 7:




Step 8:




OBD II scan tool (excluding hand held tester):

CHECK FOR INTERMITTENT PROBLEMS

Hand-held tester only:
Inspect the vehicle's ECM using check mode. Intermittent problems are easier to detect when the ECM is in check mode with hand-held tester. In check mode, the ECM uses 1 trip detection logic, which has a higher sensitivity to malfunctions than normal mode (default), which uses 2 trip detection logic.

a. Clear the DTCs.
b. Set the check mode.
c. Perform a simulation test
d. Check the connector and terminal.
e. Wiggle the harness and connector.