Hey everyone I'm having a issue with my 05 tl (auto) for the last couple days . Heres the issue.. I would get in start the car then after about a minute or two my rpm, speed ( if I'm moving ) and temp needle drop to 0. Also if my A/c is on the compressor turns off, the green light next to the gear indicator turns off, my oil life and fuel range reads dash (---). Also sometimes my lock will lock and unlock by itself ( only happens in Parking not while driving ) I tested the alternator and it read 13.9~ volts.

Any help would be great guys .

 

did you test the battery?
and did you check both inside fuse box and outside fusebox for blown fuses?

 

Check and clean all the battery connections and grounds to start. Check the ground connection to the frame as well. These cars like to display some weird symptoms when the battery connections are going bad.