P0603
Internal Control Module Keep Alive Memory Error
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0603 means
- The fault code P0603 indicates that there is an error with the internal control module's keep alive memory system. This may cause the vehicle to experience a variety of issues related to the control of various systems.
Possible symptoms
- Illuminated check engine light
- Loss of power or acceleration
- Rough or erratic engine idle
- Poor fuel economy
- Inability to start the vehicle
Possible causes
- Faulty or damaged internal control module
- Electrical wiring issues within the system
- Battery or charging system issues
- Corroded or loose electrical connections
Related parts
- Engine Control Module (ECM): ECM is the part of the car computer that controls the engine system and performance. Problems lead to poor fuel economy, engine stalling & unwanted engine vibrations
Possible solutions
- Replace the internal control module
- Check and repair any damaged wiring or connections
- Diagnose and repair any battery or charging system issues
- Clean and tighten any corroded or loose electrical connections
Free on OBD DashX
P0603 on OBD DashX
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