What are the common causes of P0603?

Corrupted keep alive memory data in the PCM. A weak or failing battery dropping KAM voltage. An open or short in the KAM power circuit. Water or physical damage at the PCM. A software or programming fault.

Check battery voltage and the PCM keep alive power feed. Inspect the PCM connectors for corrosion or water. Verify the KAM power circuit for opens and shorts. Update or reprogram the PCM software. Replace the PCM if the memory fault returns. Clear the code and retest.

P0603

Internal Control Module Keep Alive Memory (KAM) Error

System: Computer output circuits (P code)
Lamp: Check Engine Light
Category: Powertrain - Computer and Auxiliary Controls

What it means

P0603 means Internal Control Module Keep Alive Memory (KAM) Error.

Where it lives

For P0603, the description names the module as the part involved.

Check these first

Corrupted keep alive memory data in the PCM
A weak or failing battery dropping KAM voltage
An open or short in the KAM power circuit
Water or physical damage at the PCM
A software or programming fault

What to do next

Check battery voltage and the PCM keep alive power feed
Inspect the PCM connectors for corrosion or water
Verify the KAM power circuit for opens and shorts
Update or reprogram the PCM software
Replace the PCM if the memory fault returns
Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.