Coach has what looks like an OBD2 port under the dash,considering we have the mechanical 8.3 what info will I get from this port?
It is the location of the Allison diagnostic port.
And I learned last year, our age coaches have the "old" style plug. Might save some time and walking when the tech does the code scan and any reset. I had mine reset after the temp sensor wire got wet, and showed High temp. It was also explained, that if you ever get High Temp warning, the computer will disable the retarder to protect the transmission, till it is reset.