In case you are wondering why some audio adapters work with 2003s and not 2004s, check this out:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Audio Amplifier
The radio supplies low level audio signals to the audio amplifier in order to boost the signal sent to the speakers. The class 2 signal circuit allows the radio to recognize that an amplifier is present. Once the radio detects an audio amplifier, it will output low level audio signals. The audio amplifier is turned on when it receives a message via the class 2 serial data circuit indicating that the radio is on. The audio amplifier can also be a Non-Class 2 Bose amp, which was a mid year change in 2004 MY. Ensure which amplifier is installed in the vehicle.
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Klaus
Rare 2003 H2 with UM8 Integrated Navigation Radio
Skull & Bones Member since 2003