P0603: Control module keep alive memory error
Internal control module keep alive memory (KAM) error
Severity: Inspect soon
TroubleCodes.net lists stalling and rough running as symptoms, so have it inspected soon rather than assume it is cosmetic.
It gets more serious if:
- Stop: Stop driving if the engine stalls.
P0603 in short
P0603 means the engine control module found an error in its keep alive memory, where it stores learned adjustments. It then uses default settings. Aftermarket tuners, wiring faults or water in the module are the usual causes. The check engine light is often the only sign, but stalling can occur.
The keep alive memory holds learned values and needs constant power. If the module finds an error, it sets P0603.
TroubleCodes.net lists aftermarket tuning, module wiring faults, water in the module, ignition wiring interference and a faulty module as causes. Delaware lists the code as an internal control module keep alive memory error.
A 2013 Nissan Pathfinder owner quoted the same wording after an intermittent fault a workshop could not repeat.
Most likely causes
These are general causes for this code across vehicles. None is specific to one make or model.
Cause 1: Aftermarket tuning
Common general cause- Why it ranks here
- TroubleCodes.net lists tuning products first, especially on diesel trucks.
- What would change this
- Rises if a tuner is fitted. Falls if the vehicle is stock.
Cause 2: Module wiring fault or water in the module
Common general cause- Why it ranks here
- The page lists faulty module wiring and water intrusion.
- What would change this
- Rises if corrosion or wet connectors are found. Falls if dry and clean.
Cause 3: Faulty control module software or hardware
Possible — needs testing- Why it ranks here
- The page says reflashing may help when no wiring defect is found, and lists the module as a cause.
- What would change this
- Rises after wiring and power are cleared. Falls if a reflash fixes it.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Check the battery charge and cables, and look at the wiring near the module for water or damage.
IfBattery weak or cable loose, or wiring wet or damaged
It meansRepair that first and retest.
IfEverything looks good
It meansCheck for tuning and software.
Step 2: Ask whether a tuner has been fitted and have the dealer check for a software update.
Warning:Reflashing with a weak battery can corrupt the module. Keep a charger connected.
IfA tuner is fitted
It meansRemove it and retest.
IfNo tuner and software is current
It meansModule failure is possible.
Symptoms
- Check engine light
- Rough idle or stumble
- Stalling Gets more serious: stop and have it checked.
How to fix
Step 1: Check that the battery is charged and the cable ends are clean and tight.
Parts and cost context
- Engine control module (ECM / PCM):Labour varies; get a quote.
Labor varies by vehicle and shop; get a quote before you approve a repair.
Compare used part prices on PartPriceGuideOn your vehicle
NissanYour car
2013 · Pathfinder
Supported by vehicle dataOne 2013 Pathfinder complaint quotes P0603 as a KAM error after an intermittent fault.
Related codes
P0603 questions
Why did P0603 appear after I disconnected the battery?
Disconnecting power can erase keep alive memory. The sources here do not cover that case; have it checked if the code returns.
Sources and review
- P0603 trouble code definition
- ODI 11124229: 2013 Nissan Pathfinder, P0603 KAM error
- On-Board Diagnostic Trouble Codes (generic code title list)
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error