The VAD503 setup includes the PD-140DS and CY-18DR digital pads. When they are connected to the TD-27, the 1/4" RD, RDB, and SNR cables that are part of the harness are defeated and cannot be used. If you have extra pads that you're trying to connect, be sure to connect them to the 1/4" CRASH 2 or AUX 1-3 inputs on the back panel of the TD-27 with separate cables.