OBD-II code · Powertrain (generic)
P0603 Internal Control Module Keep Alive Memory (KAM) Error
The ECU detected a fault in its KAM (battery-backed memory used to store adaptations and DTCs). Often appears after battery disconnect or low battery; persistent codes indicate an internal ECU fault.
Is it safe to drive with P0603?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyBattery disconnected or voltage too low
- Less likelyECU internal memory fault
- Less likelyModule software outdated, reflash may resolve
Symptoms
- Check engine light on
- Possible limp mode or no-start
- Multiple follow-up faults across modules
- Reset/relearn may be needed after repair
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.1–4 h
- Emissions test
- Usually unaffected
- Parts involved
- Ecm, Vehicle Battery
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.