HELP!! Trailer wiring

[Motorand]

HELP!!! I just bought a 2002 Silverado 4 wheel drive 1/2 ton that has never had a towing package on it. I put a reciever hitch on it and took it in to get wired at a local pickup accessories shop. When I checked my 7 way round plug by plugging it into my trailer, everything works but my brake lights. They told me that I need to buy a wiring harness from the dealer, which I called about and found out that it costs 125.00! YIKES! Is there any other way to do this, or buy this part without spending this much for the adapter/harness?

[95Sierra2500]

You can tap into your brake lights and turn signals in at the lenses on your truck. This is not the recommended way, but it DOES work.

[asilverblazer]

The truck is prewired the harness is taped above the spare tire. Unless they quit doing that too. Where did the "shop" tap for the other wires, because it sounds like the wrong place. Also there is a fuse in the underhood electrical center you could check.

[Motorand]

Everything is hooked up for the trailer, and it all works, except the brake lights. They work on the truck but not the trailer. I have not checked yet to see if there is a wiring harness above the spare.

[pwall]

Dumb question but gotta ask.....are you sure the trailer connections are good? i.e. have you plugged the trailer into another truck to verify ?

[asilverblazer]

Just because they work on the truck means nothing for the trailer, it's an independent circuit.