ABS light and trailer harness question

Here's my first post on this great site. I hope somebody can help.

The ABS and traction lights lit up on my 2009 Tacoma, and my cruise control started shutting off whenever I used the turn signal. So I took it to the dealer. The technician said it was due to the trailer wiring harness shorting out. He disconnected the trailer wiring harness and problems went away. The dash lights went off and the cruise control started working properly again.

So, I bought a new wiring harness and installed it. Very simple job. However both problems came back with the new harness. Same issues as with the old harness.

Any suggestions?
Thanks.

 

Warranty is done I guess ?

 

What wiring harness are you using and who did the wiring?

 

I bought the new trailer harness at a local auto supply store and installed it myself. They confirmed that it is for an 09 Tacoma. It is an easy installation with T-connects. I know it is installed correctly. All my truck and trailer lights work perfectly. But the ABS dash light comes on as soon as the harness is connected.

Maybe I should try a third trailer harness just in case the 1st two happened to be defective. Stranger things have happened.

 

Best help ever.... mine had exactly the same issue. Easy fix with your help... thx to bhunts!