Question

2009 Infiniti G37 with engine code P0603, how do i repair this?

Answer 1

If the battery is not bad start by charging the vehicle's battery and cleaning the terminal, once the battery is charged and the terminals are clean and secure, erase the code. If the code comes back ON, you may have to reprogram or replace ECM

P0603 INFINITI Code - Engine Control Module Power Supply Circuit
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