Using a Guitar Hero 3 Wireless Guitar with Guitar Hero 2 (PS2): Not Compatible

You cannot. The Guitar Hero III (Les Paul) wireless guitar uses a different proprietary 2.4 GHz protocol than the Guitar Hero II (Gibson X‑Plorer) wireless guitar. The PS2 dongles are not cross‑compatible.

Why It Fails

• Different Dongles: GH2 dongle (black, rectangular) ≠ GH3 dongle (white, curved).
• Different Firmware/Encoding: The console sees them as distinct device IDs.
• No Forward/Backward Compatibility: Activision did not bridge the protocols.

Workarounds (Ranked by Reliability)

1. Use the Wired GH2 Guitar: The Gibson X‑Plorer wired controller works natively on PS2 for GH2, GH3, GH: Aerosmith, GHWT, GH:SH, GH5, Band Hero.
2. Buy a GH2 Wireless Kit: Find a used Gibson X‑Plorer wireless guitar + its specific black dongle (eBay ~$40–$60).
3. PS2 → USB Adapter + PC Clone Hero: Use a PS2‑to‑USB adapter (e.g., Mayflash) to play Clone Hero (free PC game) with the GH3 Les Paul. Best modern experience.
4. Hardware Mod (Advanced): Swap the GH3 guitar's PCB into a GH2 guitar shell, or reprogram the dongle via PIC microcontroller. Not recommended for beginners.

Bottom Line: For authentic PS2 GH2 play, source the correct Gibson X‑Plorer (wired or wireless). The Les Paul is physically incompatible with the GH2 dongle.