I replaced my factory (2512?) Xantrex modified sine wave inverter with a new Xantrex SW 2012 pure sine wave inverter when I replaced my Norcold fridge with a residential fridge. The new inverter came with a new temp sensor, but I can't crawl under the coach to run the new wire back to the inverter from the batteries. So I called Xantrex customer service to see if I could splice the new temp sensor onto the original phone wire connection that went to the old inverter. Tech said no, do not splice into the cable. Didn't explain why, but he did say the temp sensor 'doesn't do a lot' so its ok if you don't hook it up. I do know its purpose is to slightly reduce charge voltage when battery temp is somewhere in excess of 90f, but I can't recall the exact figure. I do not think the temp sensor or circuit provides any 'protection' from an overheated battery; i.e. if your battery is gonna explode due to an internal short or something, the temp sensor is not designed to save the day. So I haven't connected the new sensor to my new inverter, all seems to work ok.