2000 Peterbilt 379 high beam always on
 

Looking for info on this high beam problem. I have disconnected the blinker/high low harness on the steering wheel and the high beam light does not go off. The only way I can get it to go off is pulling the LHDL relay. Yes I have tried different relays. The wiring schematic do show a MTS module, but I cant find it in the dash area. If I could locate that and unplug it and see what happens?? I guess im looking for any advise on what to do. So for know my lights are always on bright...