Hi,
Please provide the truck details such as Still FMX14-20xx (2007, 2015,...), truck serial No. & your email address so that I am able to send the relative docs to fix this problem.
I am really sure that one of the wirings ( 2 power supply + 1 signal) is broken.
This is ONLY to be used to report flooding, spam, advertising and problematic (harassing, abusive or crude) posts.