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Ignition Unlock Circuit Rationality Check

IGNITION UNLOCK CIRCUIT RATIONALITY CHECK

WHEN MONITORED
Continuously.

SET CONDITION
One second of Run/Start above 5 volts, Unlock Status Low, and Run/ACC Status High.

POSSIBLE CAUSES
- Ignition unlock-run-start fuse open
- (F21) Ignition unlock-run-start circuit open
- Instrument cluster

DIAGNOSTIC TEST

1. IGNITION UNLOCK-RUN-START FUSE OPEN
Turn the ignition off.
Inspect the Ignition Unlock-Run-Start fuse in the PDC.

Q: Is the fuse open?

YES: Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for a short to ground condition. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 2

2. INSTRUMENT CLUSTER




Turn the ignition off.
Disconnect the Instrument Cluster C3 harness connector.
Turn the ignition on.
Measure the voltage of the (F1) Ignition Unlock-Run-Start circuit.

Q: Is the voltage above 10 volts?

YES: Replace the Instrument Cluster. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Repair the (F1) Ignition Unlock-Run-Start circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test