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Updating the ECM/PCM

ECM Updating and Substitution for Testing-'02-03 M/T models and CVT model

Special Tools required

Honda Interface Module (HIM)
- P/N EQS05A35570

Use this procedure when you have to substitute a known-good ECM in a troubleshooting procedure. Update the ECM only if the ECM does not already have the latest software loaded.

NOTE: Do not turn the ignition switch OFF while updating the ECM. If you turn the ignition switch OFF, the ECM can be damaged.

How to Update the ECM
1. Turn the ignition switch ON (II). Do not start the engine.




2. Connect the Honda Interface Module (HIM) to the Data Link Connector (DLC) (A) located under the driver's side of dashboard.

3. Do the ECM update procedure as described on the HIM label and in the ECM update system.

How to Substitute the ECM
1. Remove the ECM from the vehicle.
2. Install a known-good ECM in the vehicle.
3. Rewrite the immobilizer code with the ECM replacement procedure from the Honda PGM Tester; It allows you to start the engine.
4. After completing your tests, reinstall the original ECM and rewrite the immobilizer code with the ECM replacement procedure on the Honda PGM Tester again.
5. Do the ECM idle learn procedure