Re: 2005 Navigator AdvanceTrac Problems
I hate to say it, but if I remember correctly, code U2023 generally means a PCM problem. As electrical gremlins are hard to fault, when a bad one does occur, and reoccurs at any time without any said provocation then you can almost say a bad PCM. Not sure if you've had it tested or not, but I'd make sure the wiring harness is on tight (one Ford dealer here can't install fuses correctly!). If the wiring is in fact all good, then a new PCM might be your best, if not only option. The bad part is that installing a new PCM is best left to the dealer, as they have the proper equipment to legally transfer over the engine and VIN info.
'11 Ram Quad Cab 4x4 SXT 5.7L HEMI (stock); 48,500m
'06 Pontiac G6 GT 3.5L 220hp; 64,000m
'12 Chrysler 200 Limited 3.6L 283hp; 28,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!