The P0603 trouble code indicates an error with the Internal Control Module Keep Alive Memory (KAM). The Keep Alive Memory is a small amount of memory within the Powertrain Control Module (PCM) that stores various learned values and settings, such as idle speed, fuel trim, and transmission shift points. The error occurs when the PCM detects a discrepancy or fault in the KAM.
Internal Control Module Keep Alive Memory (KAM) Error
Code symptoms P0603.
1. Check Engine Light illuminated.
2. Vehicle may experience drivability issues such as rough idle, hesitation, or poor acceleration.
3. Stored codes related to other systems or components, as the KAM error can affect various vehicle functions.
This code is common in brands such as:: Chevrolet, Renault, Ford, Toyota, Nissan, Mercedes Benz, Honda.
Causes of the code P0603.
1. Weak or dead vehicle battery.
2. Faulty PCM.
3. Electrical issues such as loose or corroded battery connections.
4. Power interruption during PCM programming or battery replacement.
5. Faulty sensors or components causing incorrect data to be stored in KAM.
Code Solutions P0603.
1. Clear the trouble codes and see if the P0603 code returns. Sometimes, the code may be triggered by a temporary issue.
2. Check the vehicle battery and charging system to ensure proper voltage levels. Replace the battery if it is weak or dead.
3. Inspect battery terminals and connections for corrosion or looseness. Clean or tighten connections as necessary.
4. If the battery or PCM has been recently replaced, ensure that the PCM was properly programmed and that there were no interruptions during the programming process.
5. Perform a PCM reset procedure as outlined in the vehicle’s service manual to clear the Keep Alive Memory and allow the PCM to relearn values.
6. If the problem persists, it may indicate a faulty PCM that needs to be replaced. Consult a qualified technician for further diagnosis and repair.