DON'T TAKE CHANCES WITH YOUR VEHICLE'S ELECTRICAL SYSTEM!!
We have noticed an ever increasing demand to repair vehicle related tow wiring that was never installed correctly. Unfortunately, most service providers aren't as interested in long term effectiveness when it comes to your vehicle's wiring as they are in making a quick buck and getting your vehicle in and out of the shop as quickly as possible. Sure, things may work well immediately after the installation, but after some use and the passage of a little time, an improperly installed tow harness will begin to show its flaws. In some cases, it's more cost effective to replace the entire harness than it is to try and repair faulty work. With today's sophisticated vehicle electronics that have computer monitoring, great care should be taken to prevent expensive damage to the vehicle's electrical system. A person would have been better off spending a little more money up front and had the proper harness installed correctly than to pay for the same job twice over a relatively short period of time; or even worse, having to replace a control module or computer on the vehicle.
The example we are going to show you here was on a late year model Chrysler 300. The customer had the wiring installed by a local shop. After 1 year of use, the wiring harness would not work anymore. The customer tried to contact the original installer only to find out that they were no longer in business.
(Click on the images to enlarge)
In this 1st photo, arrow #1 points to an area that is very problematic. This is the point that the original installer chose to run the wiring harness out of the trunk and down to the bottom of the bumper. This not only provided a place for moisture and exhaust fumes to penetrate the trunk area, but put the delicate power module box (required on this vehicle) outside and exposed it to the elements. Arrow #2 points to a type of clip attachment that is very popular with novice installers. It allows them to clip in to the necessary wires and then plug the harness wires one-by-one into the clips and search for the proper circuit by using the trial and error method. Arrow #3 points to the loose wires that are making their way across the trunk area to the other side. We'll address the loose wire issue in another photo.
In this photo, arrow #4 is pointing to the fact that this powered module harness was connected directly to the vehicle's battery with no form of amperage protection through a fuse holder or circuit breaker. This can allow the module and/or the harness to overheat which can cause module failure (as in this case) and even a fire. Arrow #3 is pointing to the loose power wire laying on top of the battery that is able to jostle around with very little limitation.
In this photo, arrow #3 is again pointing to the problem of loose, unrestrained wires. This may not seem to be a very big problem to most people, but we have found that wires that are left loose eventually get caught on something, smashed by a heavy object, damaged by other moving parts, or burned by the hot exhaust system. Wires should always be tied up in a neat and orderly fashion to prevent damage and ensure longevity.
This photo shows a side-by-side comparison of the faulty generic harness that was removed from the vehicle and the custom harness before installation. Arrow #5 points to the integrated fuse holder on the custom harness that provides the necessary protection to the power module. Arrow #6 points to the custom connectors that are integrated into the harness that eliminate the need for probing, cutting, or splicing of the vehicle's factory harness. With only a few exceptions, a custom wiring harness is always worth the extra money to insure a quality, long lasting installation.
Compare this photo with the first photo. This is how things SHOULD look! Arrow #7 points to the vehicle specific custom connector that eliminates the need to clip in to the factory wiring. Notice that the harness is NOT ran out through the hole in the trunk to the outside. Anytime the wiring can remain inside the vehicle, that is a huge benefit. The wiring components will last much longer if installed inside the vehicle than a wiring harness that is exposed to the elements.
(On some vehicles, exterior installation cannot be reasonably avoided. In those instances, we use weather proof connections and take extra precautions.)
Arrow #8 points to a neatly tied off harness that will remain in place alongside the factory harness regardless of conditions.
Finally, this photo captures several of the quality points of a professional installation. Arrows #7 & #8 again point to the custom harness connectors and a properly tied up harness. Look at arrow #9. This points out the integrated power module mounted inside the trunk, out of the elements, and out of the way of any potential damage from regular vehicle usage. Arrow #10 points to the integrated fuse holder that protects the vehicle and the wiring harness from electrical overheating and module failure. We clearly mark the holder so the vehicle owner can easily identify the fuse and we position it in a place where changing the fuse, if needed, is easily achieved.
As you can see, there are a lot of things to consider when having your electrical system modified for towing a trailer. Let a professional towing systems provider like Long's Northwest Hitch perform your vehicle's wiring installation to avoid costly and time consuming repairs that are the result of improperly installed components.