Is there a 'VSC' light or something similar lighting up? Something similar happened on our LS430... it made one of the function lights come on (even though that function was not engaged or operational), and all of the other stuff (ABS) quit working.
Short term fix was to pull the ECU fuse and reset the computer. It would work for a while and then come back on. Long term fix was to troubleshoot the code that popped up. In this case is was something simple like a loose vacuum hose or something.
no warning lights whatsoever......
@under_psi I bet you money whoever deleted the AHC pulled the wrong fuses...
I will look for the thread, but what you are describing rings a bell in my head for sure. There is a proper way and a sloppy way to do the electrical side of that delete, and it sounds like they did it the sloppy way.
the AHC fuse is removed. the truck 'used' to have properly functioning ABS and t case lock. ive used it.....so its something that happened since ive owned.
i heard something somewhere here that a 7pin trailer harness made it malfunction.....i am going to look and try and find