The dash guage is different to the CTS. The dash is a single blue with a spade connector that fits at the back of the thermostat, it's little more than a brass stub with a pin thing on the top for a spade to slide onto. The CTS has two pins and is connected as per the DTA wiring diagram, this is also mounted at the thermostat. Can't remember if the socket if blue or black, tempted to say blue.