Engine codes P0600, P0601, P0602, P0603, and P0605

Understanding your engine code’s part 5.

 Modern vehicles are equipped with sophisticated computer systems that control and monitor various engine functions and other components. When something goes wrong, these systems generate diagnostic trouble codes (DTCs) to help pinpoint the issue. Among these, codes starting with "P0600" are related to problems with the engine control module (ECM) and the communication network between modules.

 P0600 refers to a Serial Communication Link Malfunction, meaning there’s a breakdown in the communication network between control modules. These modules rely on a continuous flow of data to operate efficiently, so when the communication link is interrupted, it can lead to various issues.

 The P0601 code indicates a problem with the internal memory of the ECM. Specifically, this code appears when the ECM performs a checksum test (a verification process to ensure data integrity) and detects a memory error.

 P0602 refers to a Control Module Programming Error, meaning the ECM has detected a problem with its programming. This could occur if the ECM’s software is corrupt, incomplete, or improperly installed.

 The P0603 code is triggered when there’s an issue with the Keep Alive Memory (KAM), which stores data such as engine timing and fuel settings even when the vehicle is turned off. If this memory becomes corrupted or lost, the code can be set.

 P0605 points to an Internal Control Module ROM Error, meaning the ECM has detected an issue with its Read Only Memory (ROM). ROM contains the essential programming that controls the vehicle’s engine, and errors in this memory can cause serious operational issues.

 Engine codes P0600, P0601, P0602, P0603, and P0605 are all related to problems with the ECM and its communication or memory systems. While some issues, like wiring faults, may be relatively simple to address, others (such as ROM or checksum errors) often require ECM replacement.

 Addressing these codes promptly is important, as the ECM controls many critical functions, including engine timing, fuel management, and even safety features. If you encounter any of these codes, it’s best to consult a professional mechanic for accurate diagnostics and repairs.