How to Update the PCM
Updating the PCMSpecial Tools Required
Honda interface module (HIM) EQS05A35570
Use one of these procedures when you have to substitute a known-good PCM in a troubleshooting procedure. Update the PCM only if the PCM does not already have the latest software loaded.
NOTE:
^ To ensure the latest program is installed, do a PCM update whenever the PCM is substituted or replaced.
^ You can not update a PCM with the program it already has. It will only accept a new program.
^ Before you update the PCM, make sure the vehicle's battery is fully charged.
^ To prevent PCM damage, do not operate anything electrical (audio system, brakes, NC, power windows, moonroof, or door locks) during the update.
^ If you need to diagnose the Honda interface module (HIM) because the HIM's red (#3) light came on or was flashing 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 PCM damage.
^ High temperature in the engine compartment might cause the 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.
^ Do not turn the ignition switch OFF while updating the PCM. If you turn the ignition switch OFF before completion, the PCM can be damaged.
1. Turn the ignition switch ON (II). 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.
NOTE: If the HDS does not communicate with the PCM, troubleshoot the DLC circuit.
3. Make sure the HDS communicates with the PCM. If it doesn't, go to the DLC circuit troubleshooting. If you are returning from the DLC circuit troubleshooting, clean the throttle body after updating the PCM.
4. If the HDS does not have the update function, disconnect the HDS from the vehicle and connect the Honda interface module (HIM).
5. If the software in the 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 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 PCM update system requires you to cool the PCM, follow the screen prompts. If you run into a problem (programming takes over 15 minutes, status bar goes over 100%, D or immobilizer indicator flashes, HDS tablet freezes, etc.) during the update procedure, follow these steps to minimize the chance of damaging the 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.
6. Do the PCM idle learn procedure.