[blktblazer04]

It sounds like your friend just hard wired your head unit into your TB. He should've have used one of the recommended harnesses to install it. I don't remember all the harness part numbers but someone else will chime in eventually.

Do not get a cap. Upgrade the battery under the hood. Do the Big 3. Increase your power and ground cables. If they still dim then add a second battery in the rear.

how do you keep the batt. in the rear charged ? this is the harness im using on my 04 LS no bose no onstar

 

[blktblazer04]

try running the wire to the ingiton fuse thats how i have my remote wire for my amp