EPC 523652.02 – Control Unit Connected to Wrong Wiring Harness Connector

EPC 523652.02 (EPC )

Code: 523652.02



This error code, EPC 523652.02, is generated when the control unit detects an erroneous signal in the circuit of the control unit identification during initialization (control unit boot sequence after the ignition is switched ON). This indicates that the control unit may be connected to the wrong wiring harness connector.


When this error is detected, the control unit may not function correctly, leading to potential issues with the overall system performance and functionality.


Verify Wiring Harness Connections:

  • Check all wiring harness connections to the control unit. Ensure that each connector is plugged into the correct socket as per the manufacturer’s specifications.

Inspect for Misconnections:

  • Look for any signs of misconnections where the control unit might be connected to an incorrect harness. Reconnect the wiring correctly if any discrepancies are found.

Check Wiring Harness Labels:

  • Ensure that all wiring harnesses are properly labeled to prevent misconnection. Labels should match the control unit specifications.

Reset and Test System:

  • After correcting any misconnections, reset the system and monitor the control unit during initialization to ensure the error does not reoccur.


Proper labeling and careful connection of wiring harnesses during installation and maintenance can prevent such errors and ensure reliable system performance.

Control Units: John Deere

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