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Updating the ECM/PCM

Special Tools Required 

NOTE:
  • Use this procedure when you need to update the ECM/PCM during troubleshooting procedures.
  • Make sure the HDS/HIM has the latest software version.
  • Before you update the ECM/PCM, make sure the battery in the vehicle is fully charged.
  • Never turn the ignition switch OFF during the update. If there is a problem with the update, leave the ignition switch ON.
  • To prevent ECM/PCM damage, do not operate anything electrical (headlights, audio system, brakes, A/C, power windows, moonroof (if equipped), door locks, etc.) during the update.
  • To ensure the latest program is installed, do an ECM/ PCM update whenever the ECM/PCM is substituted or replaced.
  • You cannot update an ECM/PCM with a program it already has. It will only accept a new program.
  • High temperature in the engine compartment might cause the ECM/PCM to become too hot to run the update. If the engine has been running before this procedure, open the hood and cool the engine compartment.
  • If you need to diagnose the Honda interface module (HIM) because the HIM's red (# 3) lamp came on or was flashed during the update, leave the ignition switch in the ON (II) position when you disconnect the HIM from the data link connector (DLC). This will prevent ECM/PCM damage.
  1. Turn the ignition switch ON (II), but do not start the engine.
  2. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
    Fig 1: Identifying Data Link Connector
    G06265741
  3. Make sure the HDS communicates with the ECM/ PCM. If it doesn't, go to the DLC circuit troubleshooting (see DLC CIRCUIT TROUBLESHOOTING ). If you are returning from the DLC circuit troubleshooting, skip step 4 to 5 and clean the throttle body after updating the ECM/PCM (see THROTTLE BODY CLEANING ).
  4. Select the INSPECTION MENU with the HDS.
  5. Select the ETCS TEST, then select the TP POSITION CHECK, and follow the HDS screen prompts.
    NOTE: If the TP POSITION CHECK indicates FAILED, continue this procedure.
  6. Exit the HDS, then select the update program, and follow the screen prompts to update the ECM/PCM.
  7. If the software in the ECM/PCM is the latest, disconnect the HDS/HIM from the DLC, and go back to the procedure that you were doing. If the software in the ECM/PCM is not the latest, follow the instructions on the screen. If prompted to choose the PGM-FI system or the A/T system, make sure you update both.
    NOTE: If the ECM/PCM update system requires you to cool the ECM/PCM, follow the instructions on screen. If you run into a problem during the update procedure, (programming takes over 15 minutes, status bar goes over 100 %, D or immobilizer light flashes, HDS tablet freezes, etc.), follow these steps to minimize the chance of damaging the ECM/PCM:
    • Leave the ignition switch in the ON (II) position.
    • Connect a jumper battery (do not connect a battery charger).
    • Shut down the HDS.
    • Disconnect the HDS from the DLC.
    • Reboot the HDS.
    • Reconnect the HDS to the DLC, and try the update procedure again.
  8. If the TP POSITION CHECK failed in step 6, clean the throttle body (see THROTTLE BODY CLEANING ).
  9. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  10. Do the CKP learn procedure.
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