From what I understand about the mycolor gauges, there are 2 light sources. One is an ambient light that sits behind the gauge face plate (general illumination) and the other is the face plate itself, which is where the actual colored light comes from. Judging by the picture, I would say that section of face plate has stopped working for whatever reason. The leds/bulbs behind the face plate can be replaced. The face plate itself can not be repaired (rather, is likely more costly and time consuming to repair than the cost of replacing the while thing). I have not had a S197 gauge pod apart, so I'm mostly assuming its construction is similar to the SN95/Edge pods, which I've done a bunch of work with.
Options.
It used to be you couldn't swap gauge pods without having the PATS done at a dealer or tuned out by a tuner. They use to have physical milage rollers built to the speedo. The S197's may be different, but I know it's a direct plug n play. The only catch may be for loading information which would likely require dealer calibration (assuming milage is stored on the gauge pod or there is still a PATS governing the pod). Unlike back in the day, the cost of a replacement gauge pod has come down significantly. ($168 + $300 core from Rockauto for example). Of course, don't send out your core until you've confirmed a successful swap and don't need the original for dealer calibration (mileage or a PATS). This is my #1 option. I feel it's the path of least resistance and will yield the best results. Just make sure you get on the phone and confirm that you're ordering the same gauge pod with mycolor, and not a non-mycolor (if you still want mycolor). Don't get a V6 pod either, the speedo and tach are different.
Another alternative would be to swap the face plate itself. The face plate should be plug n play. You could use anything aftermarket that is based on the GT pod, as long as the gauge position and count match. You may lose the mycolor feature, not sure that the aftermarket plates offer it. Personally, I'd go with a Bullit face plate since it's factory Ford and looks awesome to boot (i think they are mycolor as well). This is the #2 option, IMO.
And then there's the route you're currently seeking, which is to send out for repair. Personally I don't like this option, again cost & time. Repairing a face plate is going to involve taking layers apart and finding the culprit component (likely an LED or circuit path, the face plate looks kind of like a motherboard under the snazzy exterior, with circuit paths running through it and very very small LED's that allow for multi-color operation). I think this option is going to cause you hair loss and high blood pressure. If you were an avid DIY'er and had a bench, the tools, and knowledge to get surgical on this face plate of yours, it'd be a grand adventure and lots of pics/vid/writeup for your fellow enthusiast. I'd offer to do it myself, but I'm pressed for time most days. All I can offer is theories and an opinions with options.
The mycolor gauge faceplate doesn't have issues very often, which is why user info is limited or non-existent on this subject. As with anything when you venture into unknown territory, document and post your findings/results. Help a future you find his way.
