DTC P0603:00 [MZI-3.7]: Notes

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

DETECTION CONDITION & POSSIBLE CAUSE

DTC P0603:00	PCM keep alive memory (KAM) error
DETECTION CONDITION	Indicates the PCM has experienced an internal memory concern. However, there are external items that can cause this DTC.
POSSIBLE CAUSE	Battery terminal corrosion Loose battery connection Connector or terminal malfunction Open circuit between battery positive terminal and PCM terminal 1V Reprogramming
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