I have the CS C130 in FSX-SE and to activate the GPS flight path is very easy.
I have P3D V4.3 now and is very pleased that the C130 is included.
However, I cannot activate the GPS flight path although the panels look exactly the same. I do follow the same steps:
1. Mode selector to GPS
2. AP Power on
3. Engage on
4. Track on
And now the the AP should follow the GPS path, but nothing.
If I set the mode selector to Heading, it follows the Heading immediately.

Is their maybe a bug in the .cfg file?

Thanks for your help in advance

Thanks for your reply.

I have followed your steps exactly and still no difference. I used the very same aircraft.

When I set the heading adjuster to the GPS heading an switch the mode selector to heading, it fly the heading without any problem.

Thanks for the help so far

Is this happening with one of the LM C-130 models included as a part of Prepar3D v4.3/v4.4, or one the Captain Sim C-130 X-perience copied over to Prepar3D v4.3/v4.4?

I just did a test in the LM C-130J-30, and it followed the GPS route. I started out with a Direct To -> and then I created a route to follow, and it tracked the magenta line for both.

One other thing to add to my instructions post above (#6):

1. I created the route in the Flight Planner
After takeoff, and at a reasonable altitude, I did the following
2. AP Power ON
3. Engage switch ON
4. Track switch ON
5. Mode Selector switch to GPS
6. Make sure that the NORMAL-HEADING SWITCH is set to HEADING

All I do to get both the CS C-130's and LM C-130's to follow the route track (magenta line), is what I wrote.

As for ther CS C-130 X-perience being in demo mode, here is what I did to get it to work in P3Dv4: https://www.captainsim.org/forum/csf.pl?num=1530025759/20#20