Clearing Transponder Codes of Lost Programmed Ignition Keys

If your client has lost one or more (but not all) of the programmed ignition keys, you should rewrite the ECM/PCM with the HDS to prevent the lost keys from starting the engine. The HDS clears the transponder codes from the memory of the ECM/PCM and then stores the transponder codes of your client's remaining keys. This process, in effect, clears the codes of the lost keys, so they cannot start the engine.

Preparation

To clear the transponder codes of lost programmed ignition keys, you need these items:

^ All of your client's remaining programmed ignition keys (master and valet) for the vehicle. (This includes any master or valet keys with a T5 stamped on the shank or molded into the grip. These are duplicate keys made with the Ilco Immobilizer Key Code Duplicator.)

^ HDS with the latest software

NOTE:
Make sure the setup and time are correct before you use the HDS. Select the F12 key in the upper right corner to get the Set-up Details screen. Make sure Market: is set to USA. Select the time display in the lower right corner to get the Date/Time Properties pop-up window. Make sure the date and time are correct. For details, refer to the Honda Diagnostic System (HDS) Setup Instructions listed under Tool Information in ISIS.

^ PCM code

NOTE:
If you cannot log in to the iN on the HDS, you must retrieve the PCM code from the Immobilizer Code Inquiry in the iN.

Procedure

NOTE:
Make sure you change keys when prompted by the HDS.

1. Gather up all of your client's remaining programmed ignition keys (master and valet) for the vehicle. Set aside any T5 keys.

2. Connect the HDS to the 16P data link connector (DLC).

3. Insert a programmed ignition key into the ignition switch, and turn the switch to ON (II). Turn on the HDS, then log in to the iN.

4. At the screen prompts, enter the VIN and the odometer reading, and then verify the correct date and time.

5. From the System Selection Menu screen, select IMMOBI.

6. From the Mode Menu screen, select Immobilizer Setup.

7. From the Immobilizer Test Mode Menu screen, select Add and Delete Keys.

8. From the Add and Delete Keys screen, select Delete Keys.

9. From the Delete Keys screen, select Begin to Delete Keys.

10. Follow the on-screen prompts. If your HDS is not logged in to the iN, you will have to enter the PCM code you have retrieved from the iN Immobilizer Code Inquiry to proceed. When you are finished, turn the ignition switch to LOCK (0), and then turn off and disconnect the HDS.

11. T5 keys only: Start the engine with each of the T5 keys you set aside in step 1.

^ If all of the T5 keys start the engine, the transponder codes are already recognized by the ECM/PCM and the immobilizer procedure is complete.

^ If any of the T5 keys do not start the engine, go to step 12.

12. The HDS accepts only one key of a certain transponder code. If the total number of nonprogrammed T5 keys plus the keys you entered is greater than six, use the key code duplicator to recode the additional T5 keys to match an existing transponder code.

NOTE:
The HDS shows you the number of transponder codes stored in the memory of the ECM/PCM. If any of the keys share the same transponder code (as might be the case with a T5 key), the number of codes shown may be fewer than the actual number of keys.