P0381 WAIT TO START LAMP INOPERATIVE

When Monitored and Set Condition:

When Monitored: Ignition on.
Set Condition: The cluster sends a signal to the ECM that it has detected a failed wait to start lamp.

POSSIBLE CAUSES

• WAIT-TO-START LAMP STAYS ON ALL THE TIME
• WAIT-TO-START LAMP DRIVER CIRCUIT SHORTED TO GROUND
• WAIT-TO-START LAMP DRIVER CIRCUIT OPEN FROM ECM TO CLUSTER.
• FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
• WAIT-TO-START LIGHT BULB
• ECM DRIVER CIRCUIT OPEN
• WIRING/CONNECTOR PROBLEM
• ECM

DIAGNOSTIC PROCEDURE

1. Turn the ignition off. While watching the wait-to-start lamp, turn the ignition key on. Did the wait-to-start lamp light?
   Yes --> Go To 2
   No --> Go To 4
2. Turn the ignition off. While watching the wait-to-start lamp, turn the ignition key on. Does the wait-to-start lamp stay on all the time?
   Yes --> Go To 3
   No --> Wait-to-start Lamp operating normally. Test passed. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
3. Turn the ignition off. Disconnect the ECM harness connector. Check connectors - Clean/repair as necessary. While watching the wait-to-start lamp, turn the ignition key on. Did the Wait-to-start lamp light?
   Yes --> Repair Diesel Wait-to-start Lamp driver circuit for a short to ground. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
   No --> Test Complete.
4. Turn the ignition off. Disconnect the ECM harness connector. Connect a jumper between the ECM Wait-to-start Lamp driver and a good ground. Did the Wait-to-lamp illuminate?
   Yes --> Go To 5
   No --> Repair the open Wait-to-start lamp driver circuit open from ECM to cluster. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
5. Turn the ignition off. Remove the cluster. Turn the ignition on. Using a 12-Volt test Light, check the Fused Ignition Switch Run/Start circuit. Is the light illuminated and bright?
   Yes --> Go To 6
   No --> Repair the open fused Ignition Switch Output circuit Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
6. Remove and inspect the Wait-to-Start Bulb. Is the Bulb Ok?
   Yes --> Go To 7
   No --> Replace the Wait-to-Start Bulb. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
7. Measure the Wait-to-start driver circuit at the ECM harness connector. Is the voltage above 10.0 volts?
   Yes --> Replace and program the ECM in accordance with the Service Information. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
   No --> Go To 8
8. Using a schematic as a guide, inspect the related wiring and connectors for problems. Check the Fuses. Were any problems found?
   Yes --> Repair as necessary. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
9. Test Complete Repair as necessary. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).