2009 GMC 8100 with engine code P0856

Question

this code is on a medium duty transit coach with a 8100 engine and a allision 2200 transmission. When the code apears it will block all comunication with all the other systems in the bus

Answer 1

Hi there,

This code indicates an issue with the electronic brake control module. Here is some info for you.

P0856 GMC - Traction Control Torque Request Circuit Malfunction
Read more: https://www.autocodes.com/p0856_gmc.html