Nissan MIL 'ON' DTC

This applies to a MIL ON with DTC P0603 (ECM power supply) on a variety of 2006-2009 Nissan vehicles.

If you have a MIL “ON” that has a DTC P0603 stored in the ECM,

* Perform the diagnostic steps in this TSB first.

* This DTC may have stored due to a series of previous low battery voltage, dead battery or battery terminal disconnections.

* DO NOT perform any other diagnostic procedures or repairs for this code until you have performed the ones in this bulletin.

1. Connect CONSULT III to the vehicle.
2. Turn the ignition switch “ON,” but do not start the engine.
3. Check for DTCs. Confirm that DTC P0603 I stored. If P0603 is not stored, this TSB does not apply. If additional DTCs are stored, document the DTCs before proceeding.
4. Erase all DTCs. Confirm that ENGINE has no DTC stored.
5. Turn the ignition OFF. Wait exactly 5 minutes after the display changes from “No DTC” to “Error.” This waiting period is necessary for the ECM to completely shut off. Do not disconnect either battery cable at any time during this procedure.
6. Turn the ignition to ON but do not start the engine. Wait 10 seconds after the display changes from “Error” to “No DTC.”
7. Repeat Steps 5 and 6 five more times to complete the system check. If DTC P0603 does not display after the system check, this indicates that P0603 was caused by a series of previous low battery, dead battery or battery terminal disconnections. This also confirms that the vehicle harness, connections and ECM are operating properly. Do not replace the ECM.
8. If DTC P0603 does display after the system check, a claim may need to be submitted. Refer to the appropriate Electronic Service Manual for further repairs of DTC P0603 using ESM procedures.