ABS light tripped by towing

This one got me, could use Xpert advice. Just installed a an OEM hitch on my 09. Used a lighting kit that plugs into the factory tails lights. So the first time I plug my trailer plug into the harness, all is good. Trailers lights functioned....but....the ABS and anti skid dash lights came on. I put her in park and holky shnikees, it was locked in park. Did the overide thingy to get her in gear but lights still on. Called dealer, they said brake swicth. I checked all the fuses, good to go. Decided to kill the electrical and disconnected the negative and walla... lights go off. Now I haven't plugged the trailer back in yet as it is dark but was curious if anyone has some insight as to what happened? Course the dealer wants to pull the engine, swap out the rear end and replace all the glass....if you know what I mean. cha-ching!!! Help and thanks.

 

Had a similar experience. Installed a curt t-harness. No trouble for almost a year, then I start her up one day and the ABS and traction control lights on
the dash come on and stay on. No brake lights either. Took it to the dealer
(a 2012 taco) and they replaced the brake light fuse and the switch under the brake pedal. Was told the problem might be the aftermarket harness.
I thought that was b.s. but I also noticed that the dash lights would stay on after I shut the ignition off until I took my foot off the brake. I disconnected the harness and the problem disappeared! I'll take a multimeter to the harness soon and find out if it shorted out in the 'protect module'. I used wire loom throughout when I installed it so there's no issue anywhere else
on the harness. I'll post more later.

 

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