Hello, long time lurker but newbie poster here. I'm a little worried and have come for some reassurance and direction - hopefully. Both, a Canadian Lexus dealer and the good people at etrailer.com have warned me that installing a splice-in trailer wiring harness (like the Tekonsha one I have) can lead to assorted electrical and electronic issues in my new-to-me '05 430.

I had the dealer (my first trip there) install the Curt hitch and thought they would do the wiring too but the service manager informed me that his master tech would not complete the job because of potential electrical issues. When the manager learned there was no OEM harness to sell me, he reconsidered and said the shop would indeed install the wiring but could not guarantee it would be problem free.

Being a little skeptical, I double checked with etrailer.com who had recommended the Tekonsha power module. They replied that, yes, they had received reports that the splice-in harnesses had caused electrical/electronic problems in high end cars and to use the Tekonsha product at my own discretion. I wasn't expecting that answer.

I've read through the forum threads about trailer hitches and wiring and it seems that a number of members have successfully installed (and had installed) aftermarket trailer wiring with no damage to their car's electric/electronic systems. Should I be worried about the warnings from the dealer and etrailer or, just bite the bullet, and go to a business that specializes in trailer hitch/wiring and hope for the best?

Any advice would be greatly appreciated. Thanks.