thanks for the suggestion CdnoilRAM i will give that a try
as for the trailer test, 2 more trailers are not recognized.
i guess i will now see if someone has a TBC i can swap for another test and determine if its the TBC or the wiring.
does anyone know how i could test this theory another way? the only person i can think of that i might be able to call is the guy i bought the TBC from on Kijiji.ca. He has the exact same model i saw in his truck, but hes located far away