Trailer Breakaway Switch Not Working? Try This!

Every week we take a look back at the RV Doctor Gary Bunzer's answers to your tough questions. He has been providing insight into troubleshooting, repair and preventative RV maintenance since 1968.

Dear RV Doctor, for some unknown reason the breakaway switch on my travel trailer no longer applies the brakes when I pull out the activator. The trailer brakes work when I apply the brakes in my truck. Any suggestions as to how to troubleshoot my problem? — B. Prim

Good question, Bill. Here's a quick list of things to check when your trailer breakaway switch is not working:

• The voltage source for the breakaway switch is supplied by the trailer battery system, not the truck battery, so the first thing is to do is check that the battery bank on the trailer is fully charged.
• If the voltage is indeed sufficient, there could be an open between the brakes and wiring of the breakaway switch, or possibly a faulty ground connection on the trailer. Check for continuity to be sure. It just might be necessary to run a new conductor.
• Also, verify there is no fuse located in that circuit. There could be an auto-reset circuit breaker, but never a fuse.
• It could also very well be a worn out or corroded breakaway switch causing the problem. I wouldn’t recommend trying to clean or refurbish a breakaway switch. As inexpensive as they are, simply replace it if it is deemed the culprit.
• Additionally, to be sure any breakaway switch is functioning properly, raise each tire off the ground, one at a time. Spin each tire and pull the activation pin. Each tire and wheel assembly should immediately lock up when the pin is pulled.
• Finally, all brake assemblies on the trailer should also be adjusted properly. I offer some quick tips below, and you should refer to your owner’s manual for the specific details.

I do recommend all serious trailerists consider an upgrade to Lippert Forward Self-Adjusting Brakes so manual brake adjustments are never required.

Brakes on both your tow vehicle, travel trailer and fifth-wheel RV should be checked and adjusted on a regular basis to ensure good performance and safe braking while you travel. Be sure to make necessary adjustments and replace damaged or worn parts before its too late.

• Newly installed manually adjusted brakes should be adjusted after the first 200 miles of operation when the brake shoes and drums have “seated.” After that, they should be adjusted once a year or as use or performance requires.
• In addition to proper brake adjustment, proper wheel bearing lubrication is essential. Travel trailer and fifth-wheel RV wheel bearings should be lubricated every 12 months or 12,000 miles.
• Check your owner's manual for specific recommendations and step-by step instructions on how to pack wheel bearings and adjust brakes. Instructions and manuals are generally available from the axle manufacturer.
• Packing wheel bearings is a dirty job. You might not want do it yourself. But, knowing how to do it will help you appreciate what you are paying for at the shop.

I'll mention one more time, if you want to skip the hassle of having to adjust your trailer brakes, check out the Forward-Self Adjusting Brakes from Lippert. These brakes adjust during every forward stop, providing up to 50 percent better braking distance!

All effort is made to ensure the correctness of Gary’s responses; however, not all responses will apply in every instance. Some situations may mandate a visual inspection and further hands-on testing. It is imperative that if you choose to follow any instructions or procedures outlined in The Doctor’s Orders column, you must first satisfy yourself thoroughly that neither personal nor product safety will be compromised or jeopardized. If you are in doubt or do not feel comfortable about a procedure, do not continue. Simply call your local RV service facility and make an appointment with them. Remember, the advice, recommendations and procedures offered by The RV Doctor are solely those of Gary. They do not necessarily reflect the opinions, procedures and recommendations of Lippert, this publication or any of its advertisers.