Brake contoller showing 4 volts on the connector pin all the time

Its your brake light switch which also kills your cruise control

Look in your owner's manual, or on door post info sticker.

It sounds like someone messed up to me! Apparently, the brake controller got wired into an ignition circuit that it should not have gotten wired to. When accessories are added to a vehicle, it is extremely important that the vehicle wiring diagrams are used so that you know EXACTLY what you are tying into. Some of the Chevy trucks that are sold with trailer towing packages already have the wiring for brake controllers under the dash. This makes installation easy and is already tied into the correct things.

Also see my comments on related subjects HERE

It sounds like you lost a ground.
check traier hookup first.
Probably not the controller.
P.S. There are multiple fuses for this setup. check all ! ! !

Hello! Place a 1/4 watt, 50 ohm resistor in series with the +12 battery feed to the trailer LED brake lights...Each LED drops 3.6 Volts...You can run a maximum of 3 LED's per resistor...If you have more than 3 LED's run them in parallel with each set of 3...Each run of 3 requires it's own 50 ohm resistor...

Guru.....saailer


I’m happy to help further over the phone at https://www.6ya.com/expert/david_6df67de3b14de867

check to see if it has a tow package. look under the rear bumper area for a t-plug. take out the t and plug direct. those can loose contact.

you should not have voltage unless you apply the brakes on the vehicle or the brake controller. the only constant voltage you should have is the charge line on the 7-way.

Call the dealer and tell them your concerns so that they may troubleshoot and correct the problem. They should have checked it themselves to insure they did a proper job.

Have you Checked the Harness under the Rear of the Bed for the Tow Package? These Truck usually have the Plug Harness installed from Factory and can sometimes come Undone.

You will need to replace the turn signal switch, this is a common problem on these trucks, have fixed it on a family members chevy silverado.