P0603 — Internal Control Module Keep Alive Memory (KAM) Error
Category: Powertrain Severity: Medium
Updated:
DTC code P0603 means: Internal Control Module Keep Alive Memory (KAM) Error. It falls under the "Powertrain" category, with an estimated severity of Medium. Common causes include eCM/PCM software not programmed correctly or corrupted, low or unstable battery voltage during a previous update and internal ECM/PCM hardware fault; it's worth confirming the diagnosis before replacing parts.
Possible causes
- ECM/PCM software not programmed correctly or corrupted
- Low or unstable battery voltage during a previous update
- Internal ECM/PCM hardware fault
Symptoms
- Check engine light on
- Erratic engine behavior or stalling
- Other modules may also show faults
- Vehicle may fail to start in severe cases
How to diagnose it step by step
- Check whether the battery was disconnected.
- Check the ECU's constant power feed.
- Clear the code and see if it returns.
- Repair or replace the ECU if it persists.
How to fix it
This code points to the engine computer itself. Check battery voltage and connections first (a weak battery during a software update is a common cause). If the fault persists, the ECM/PCM usually needs reprogramming or replacement at a specialized workshop or dealer.
Estimated repair cost
$0–1,500.
Frequently asked questions
What does DTC code P0603 mean?
Internal Control Module Keep Alive Memory (KAM) Error.
Is code P0603 serious?
Severity Medium. Not urgent, but worth diagnosing to avoid bigger damage.
Can I keep driving with code P0603?
Yes, if it only appears after a battery disconnect; if it persists, get it checked.
Related codes
P0602 P0604 P0601 P0605 P0600 P0606 P0615 P0620 P0627 P0641
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