2014 thor palazzo freightliner chassis

I have a 2014 thor palazzo with cummins engine, allison trans, customer had brought it to our shop ro diagnose SPN 2623 FMI 4, accelerator pedal problem, rv going into fail safe mode while driving mostly when taking off from a stop and accelerating, we have replaced the accelerator pedal and the problem went away for about 3 months, this thing came back with a same issue, I have checked all the signals, grounds and 5v reference, all seemes to be ok both signals work, and the problem is still there check engine wont clear and same codes is present as active, has any one experiance this and what would be the next step, any help greatly appreciated.

 

You were correct, I disconnected the plug and one of the pins was pushed back looks like it happened during assembly, no corrosion though, I repaired the pin, and the coach is running great no more check engine, thank you.