T5 sedan with 192,000 miles. I do all my own maintenance on my car and this one I can't figure out. This does not seem to happen in the winter, just started up again here in MN a month ago. Please help!

Power train all seems fine - new alternator tests 14.2 v when running - replaced alternator 2 yrs back. Fuses intact. Battery 2 yrs old, tests 12.6 on standby consistently. I've already had the ETS module replaced under that extended warranty, and have a check engine light that has been on for a while but with no running problems - I'm too cheap to replace the 2nd o2 sensor. Replaced timing belt last year, bilstein shocks/struts all around, K&N air filter. Mechanically my engine is very healthy. Recently pulled entire dash out to fix creak which came from 1 of those 4 plastic mounts breaking. (have photos of entire process if anyone is interested??)

After warmed up, several dash lights will come on in different combinations and frequencies on the right side array. Up arrow will flash, other lights come on and either stay on or go off after a time in no particular pattern: skid protection light, brake pressure light, and a couple others on the right side that will come on. Occassionally the speedo will drop to zero when I'm at highway speeds and stay at zero for a while - then sometimes come back up to 60 - when this happens my odometer also goes to -------, then restores to accurate mileage again. When any of these lights come on my cruise control does not work. Sometimes it will settle down to just one light or just the flashing arrow.

When this happens my transmission will not shift correctly, so I'll come to a stop and it will try to start me out in 4th gear - my theory is that since the speedo is not sending it any information it cannot decide how to shift properly since that control is likely electronic? At times even manually shifting the selector down to L will not allow the trans to start out in 1st or 2nd gear like it should. No driveability/running problems, just transmission control problems and those lights on the dash.

I'm thinking this is a grounding issue? Last month when I tore my dash apart to fix that infernal creak on the passenger side I noticed that the harnesses for the wiring underneath my center console by the OBDII port were full of old drips from my morning coffee which sits in the pull out cup holder and must have dripped through the seams and onto a couple connections there - I've cleaned all of those thoroughly and slid them in and out to ensure clean connections - problem was still there.

Any suggestions?? I'm downloading the 70mb manual pdf with wiring diagrams and thinking I'm going to try to trace every single system to where it grounds to see if theres some common ground (horrible pun - unplanned).