Error code occurred during ECU upgrade (5021-10-7000, 5021-81-7000)

✅ Symptom

An error occurred during the ECU upgrade process:
Error Code: 5021-10-7000

✅ Cause

This error may occur in the following situations:

• The vehicle does not have the corresponding ECU installed.

• The ECU fails to respond due to internal failure or other issues such as communication errors.

🛠️ Solution

If the corresponding ECU is not installed in the vehicle:

• In this case, the vehicle is not eligible for the ECU upgrade, and the upgrade cannot be performed.

• Please first verify whether the ECU is actually installed in the vehicle.

If the ECU is installed but the error still occurs:

• It is possible that the ECU is completely unresponsive due to internal failure or communication issues.

• In this case, try using the diagnostic function of the same vehicle system to check whether the ECU is operating normally.

• If the same error (5021-10-7000) continues to appear even after retrying the upgrade, the ECU may be irrecoverable.

• In such cases, please contact the manufacturer for further technical assistance.