This TSB applies to Infiniti’s 2006-2012 G37 (and can apply to a host of other models). If the MIL is on with DTC P0603 stored in the ECM, this may have been set due to a previous low battery, dead battery or battery terminal disconnection.
1. Connect CONSULT III to the vehicle and confirm that DTC P0603 is stored.
2. Erase all DTCs.
3. Turn the ignition off and wait exactly five minutes after the display changes from “No DTC” to Error.” NOTE: Do not disconnect either battery cable at any time during this procedure.
4. Turn the ignition on but do not start the engine. Wait 10 seconds after the display changes from “Error” to “No DTC.”
5. Repeat steps 3 and 4 five more times to complete the system check.
If DTC P0603 does not display after the system check, this indicates that the DTC was caused by a series of previous low battery voltage, dead battery or battery terminal disconnections. This also indicates that the vehicle harness, connections and ECM are operating properly.