802 refers to a canbus communication error. This is a very generic fault code in that the actual fault can be one of many potential problems. As the machine powers up the interface controller, the traction, steering and hydraulic controllers communicate on the canbus as part of the power up sequence. Usually 802 appears if one of the controllers does not respond. Only this week I had the same error and the fault was in the right hand traction controller. Other potential faults are a broken wire or a canbus bad termination but more often one of the controllers is the cause.