How to Obtain the Audio Unit Serial Number

WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.

To obtain the audio unit serial number on a vehicle, do following:

NOTE:

This procedure can only be done when the power has been disconnected from the audio unit, and the audio unit displays CODE when the audio unit is turned on.
If the audio unit does not display CODE when turned on, remove the No. 1 fuse (15A) from the under-dash fuse/relay box for 1 minute, then reinstall the fuse.
To obtain the audio-navigation unit serial number, refer to ECU info in the navigation system diagnostic mode (see UNIT CHECK (QUICK CHECK) ).

Turn the ignition switch to ON (II).
Make sure the audio system is turned off.
Press and hold the preset No. 1 and No. 6 buttons.
While holding the buttons, press the PWR button (Except DX model) or the VOL PUSH PWR knob (DX model) to ON.

Fig 1: Identifying PWR Button, No. 1 And No. 6 Buttons (Except DX Model)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 2: Identifying PWR Button, No. 1 And No. 6 Buttons (DX Model)
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Release the buttons, and the self-diagnostic begins (for 20 seconds).
The display shows an 8 digit number (example 12345678).

Fig 3: Screen Display - 8 Digit Number (12345678) (Except DX Model)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 4: Screen Display - 8 Digit Number (12345678) (DX Model)
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Use all 8 numbers as the serial number when using the Interactive Network (iN) to retrieve the 5 digit anti-theft code.
To end the self-diagnostic function, turn the audio unit off, or turn the ignition switch to LOCK (0). The self-diagnostic function also ends if there is no interaction with the audio unit for 20 seconds.