I thought the resistor next to the transistor was the current limiting resistor but now I am not sure. Should I add a resistor between the anode and 5V?
Also the serial monitor doesn't print out any bytes from this bit of code.
Serial.print("Received BT: 0x");
if (byte1 < 0x10) Serial.print("0"); Serial.print(byte1, HEX);
Serial.print(" 0x");
if (byte2 < 0x10) Serial.print("0"); Serial.print(byte2, HEX);
Serial.print(" 0x");
if (byte3 < 0x10) Serial.print("0"); Serial.print(byte3, HEX);
Serial.print(" -> ");