FL Cascadia Unresponsive Accelerator in low gears

2008 Freightliner Cascadia DD Series 60 Engine. Accelerator is unresponsive (won't even rev, no change in RPMs) in low gears (1,2). Hooked up to DDDL No Active codes related to engine, only one for stereo.

• System Diagnostic Code #5 - Special Instructions (S155/14) previously active
• Particulate Trap Outlet Gas Temperature Bank 1 - Data valid but above normal operational range (S320/0)
• Variable Nozzle Turbocharger (VNT) Mechanism - Data valid but abovenormal operational range (S147/0)

anyone ever experience something similar?

 

I guess it's something electrical, the weirdest part is that it happens only in the low gears.

 

** UPDATE ** After sending it to the dealer, all they could offer was that this issue was occurring after the traction control was being triggered due to a wheel spin being detected. What they couldn't tell me was why the wheel spin code was coming up. The module was tested and everything checked out. I contacted Meritor Wabco and explained the problem to them, they advised that I should unplug the ATC valve. After requesting the dealer do this, they were unresponsive, I finally got fed up and went to get it from the shop. I recalled describing this to my dad, who told me to check all the tires make sure they were the same size. I get there, the unit had all 11.24.5's and one 24.5 lo pro. Changed the tire to match the rest, released unit, problem solved! Hope this helps someone else.