Your TCU does not support Bluetooth handsfreee, even though the sticker might say BT on it. After Q4/2004 BT handsfree was added. Before that the BT was used exclusively for WDCT handset.

You may not be able to use your SIM as the network might be 3G only. Does your network support GSM 800/1800?

US TCUs are usually CDMA2000 (without SIM card). Yours might be GSM850/1900.

Are there any marking indicating if it is EU 900/1800 or US 850/1900 GSM on the TCU sticker?