Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer has a special memory that helps it remember important settings even when the car is turned off. This error means there's a problem with that memory.
The Keep Alive Memory (KAM) stores data that helps the engine control module (ECM) optimize performance. If there's an error, it can affect how the car runs.
The P0603 code indicates a malfunction with the Keep Alive Memory (KAM) in the engine control module (ECM). This memory stores adaptive data and settings that help the ECM manage the engine's performance. An error here can result in loss of stored data, affecting engine efficiency and performance.
• Check Engine Light is on
• Poor fuel economy
• Erratic engine performance
• Battery disconnection
• Faulty ECM
• Poor electrical connections
ECM: Engine Control Module
KAM: Keep Alive Memory
• Check battery connections
• Inspect ECM for signs of damage
• Perform a diagnostic scan to check for additional codes
• Reconnect or replace battery cables
• Repair or replace faulty wiring
• Replace ECM if necessary
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $1,000
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular battery maintenance
• Ensure secure electrical connections
• Avoid frequent battery disconnections
Engine Performance
• Avoid disconnecting the battery unnecessarily
• Regularly check battery health
Check if the ECM is covered under the vehicle's powertrain warranty.
This code has been common in vehicles with aging electrical systems or frequent battery disconnections.
Moderate – It should be addressed to prevent performance issues.
Driving with this error may not be illegal, but it can affect vehicle performance and emissions.
• Vehicle parked with engine off
• Battery voltage stable
The ECM is usually located in the engine compartment or under the dashboard.
Q: Can I drive with a P0603 code?
A: Yes, but it may affect your car's performance and fuel efficiency.
Q: Will disconnecting the battery clear the code?
A: It might temporarily clear the code, but it won't fix the underlying issue.
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