P0602 Control Module Programming Error

P0602 points to a control module programming error. The module reports that calibration, programming, or configuration data is invalid or incomplete.

Code details

Generic OBD-II · P0

System: Computer
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not replace the module before checking programming state and calibration compatibility; reflash or configuration may be required.

Symptoms of P0602

Check-engine light, sometimes with several unrelated codes at once.
Warning lights, a no-start, or intermittent electrical faults.
Communication or module-reset problems on a scan tool.

Common causes of P0602

Low battery voltage, poor grounds, corroded connectors, or blown fuses.
Wiring or network (CAN bus) faults between modules.
A module software/programming issue, or rarely a failed controller.

Useful checks before replacing parts

Verify battery voltage stability, module power and ground, programming history, and whether recent flashing or tuning was performed.
Check service bulletins, calibration availability, immobilizer or configuration requirements, and module part-number compatibility.
Confirm the code returns after voltage and connector checks before planning reprogramming or controller replacement.

Related OBD-II codes

These nearby computer entries can help compare wording and pin down the fault area.