viper 5901, 2009 ford fusion

Just wanted to offer an update here. I am still having the same problems as stated in the original post, and even now my remote is acting funny. Occasionally (actually more often than not), the remote will not receive a transmission back to it giving me confirmation of the commands (lock, unlock, remote start, etc) I don't think it's a range issue, as I have walked far away from my car and still had success. It seems like if the car has been sitting for a couple hours with no activity, that's when it stops sending/receiving the signal back. Anyway, my shop is ordering me a new 5901 system. I've lit a fire under them so to speak, so we'll see what happens.

Here's an update, thanks to all who helped. As I said, the shop ordered me a brand new unit. They replaced everything for me, and hoooked the rear defroster up to its dedicated switch. Temperature now reads as accurate as it seems it is going to get, rear defroster is turned on with the correct button and I am not having any issue with the remote receiving signals back (I think this was fixed with the antenna replacement) No complaints anymore.