Trailer Brakes Would Lock Up without Warning and then Stopped Working with 2000 Chevy Silverado 2500

Question

Question:

Im trying to fix an issue with my truck and trailer/s. I have a Year 2000 Chevrolet Silverado 2500 LS body style. This is a 6.0 engine V8, short box, extended cab truck with third door on the righthand side. Im trying to address trailer plug issues and you may have the products to help me fix them once and for all. Really bad issue started happening a few months back when I had a gooseneck trailer connected. Some times the breaks didnt seem to work much and then you would press the brake pedal and the trailer would lock up and cause a major jerk in the pickup. Now, the trailer brakes do NOT work at all nor-does the brake indicator show a little green light when you connect the trailer. This pickup has a Tekonsha controller in the cab. 1 Do they go bad or do I more than likely have a wiring issue on the rear? 2 I have a 6 prong connector on the rear bumper and I did see one wire broke off going into that plug. That should not necessarily impact the gooseneck as it plugs into a 6 prong in the bed of the truck. This rear bumper plug has been replaced before so I need something different. 3 Was wondering if possibly there is a short in a brake light wire or something that sometimes was jumping juice to brake wire which maybe could cause the lockup issue? It was not constant. So the rear lines have been spliced into in the past to get multiple plug end. Is there a way/do you have a new harness that would maybe be able to replace the rear 4foot or so of wiring harness? not sure if that is possible or if wires come all the way from the engine compartment back. Id also like some sort of sealed 6 prong plug for the rear bumper so I can avoid all the junk that is thrown on the back bumper. Ive even seen a video about replacing a 4 prong junction box piece located above the spare tire. Not sure if that is ever an issue. Truck has 218,000 miles on it and I travel a lot of gravel roads. Any help would be appreciated as I REALLY need brakes when pulling equipment/loads on that gooseneck.

asked by: Daniel

0

Expert Reply:

To start, brake controllers can fail over time or if they get shorted out by faulty wiring so either scenario is possible.

The wire that is broken off could be a factor, especially if it is the ground wire. It could also mean that there are other issues with the other wires or where they attach to the back of the connector so you will want to inspect the connector inside and out and make sure there is no corrosion, frayed wires, or wires that are touching.

In-bed wiring is usually tied into the trailer wiring at the rear of the truck so it very well could be related. You will also want to check the wiring and connector in the bed of the truck the same as at the rear of the truck. Many times dirty or corroded trailer connectors can cause these sorts of problems.

If the stoplight or CHMSL fuse was blown then the brakes would not do anything at all with the brake pedal. but if the wiring connection to the brake controller is compromised that could cause problems. Another possible issue is the settings on the controller. Depending on the controller you are using it may have a leveler knob that, if not positioned straight up and down, can cause all sorts of interesting things to happen. Also, make sure the controller is not tilted or turned to the side and that it is mounted within its range specified in the instructions.

You will also want to check the trailer side wiring and connector and make sure it is free of corrosion inside and out. Look for any pinched, frayed, or damaged wires on the trailer and make sure all of the grounds are attached to clean and corrosion free bare metal surfaces.

There are ways to test the brake controller too. In the truck cab you will need to sever the blue wire several inches from the back of the controller. Then use a circuit tester such as # PTW2993 to test the end of the blue wire coming out of the controller. It should only have power when you apply the manual override. If it shows power at idle, then there is something wrong with the controller and it will need to be replaced.

You can visually inspect the magnets and if you can see the copper windings coming through the magnets will need to be replaced. To further test the magnets you can follow the help article I have linked. I have also included some help articles on testing and troubleshooting brake controllers for you.

If you do need to replace the in-bed connector and the truck did come with a factory 7-Way (the center pin counts) then you could use # 41157. If you wanted to replace the 7-Way at the back of the truck you could use # HM40975 which is a 4- and 7-Way in one. I have linked installation videos of these parts for you.