I know this is an older post, but I’ll chime in to add to what Steve did to maybe helps others.
A few things:
1. You DO want to test this breakaway switch from time to time. Every 6 months is not too much, actually 4 times a season is better. Some have a little rubber O ring in them to keep the water out that gets really stuck in bad sometimes and it pulls really hard the first time. Then the next times it is easier, until time ticks away again and it starts all over again. I put silicon spray on mine to keep the O’ring from over swelling and sticking. I have heard and can believe, that some of these plastic tipped ones, that if they are not tested often get so stuck in that they rip the plastic end off when pulled and never pull out the switch.
2. Most brands recommend replacing the switch every 5 years. Assuming it is a corrosion problem.
3. Now to the danger on pulling the switch. Well depending on how you do it there can be some damage to your TV brake controller. DO NOT test the break away while the 7 wire is plugged into the truck. By puling the breakaway, it puts a full 12 volts plus and into the brake wires and applies full brake power and won’t stop until the switch is replaced, the battery unhooked or the battery goes dead. This voltage can back feed into your brake controller and do it damage. Unless you know for sure that your brake controller has a high power diode or other form of self back feed protection, unhook the truck 7 wire first.
4. Like Steve said, do not leave the breakaway pulled from a long time. Activating the switch applies full power to the brakes and will over time drain the battery or may over heat the brake coils pending how old or style you have. The coils are not made for 100% continuous duty cycle. Now how long is too long. Well when you are sitting at a red light and your foot is the brake, pending your brake controller, a lot of brake controllers still put out power to hold the TT. You could be there few minutes pending the traffic light. This happens all the time. So a long time means like many minutes of time. Like 5 to 10 minutes. This is way more then you ever need to do the test.
5. If you want to fiddle with the switch to un-stick a stuck one, just unhook the battery first and 7wire plug from the truck, then it can be out all day long and not hurt anything.
6. Now how to test if the brakes and switch actually do something. Here is one method that I use. Just because the switch is pulled out does not mean the contacts are not corroded from actually working.
On level ground, and ideally gravel, hook up TT and truck the normal way with the WD hitch etc. BUT leave the 7 wire plug unconnected.
Pull the breakaway pin. Get in the truck. Put it in gear and very, very slowly just try to creep forward. You should feel the TT brakes all locked up after about the attempt of 1 to 2 inches forward movement and it not wanting to go at all. Then stop. Get out, pop the pin back in, and try to again. It should now coast free.
7. If you do this on loose gravel, a very short drag test, about 2 to 4 inches or someone spotting the wheels, you should see all 4 wheels lock or have dust piles in front of each tire. If all 4 are not locking, (that is if you have 4 wheels, on single axle, only look for 2 wheels
) then you have a brake problem that needs to get fixed. NOTE: If the breakaway fails this test, hook up the 7 wire and try from the brake controller to do a lock up drag test on all 4 wheels. It may not be the actual brakes as it may be the switch.
8. On electric brakes the trailer has to move forward some small amount before the brake will actually lock. The magnets only energize when standing still. When the TT rolls forward the linkage magnetically coupled then mechanically engages the brakes.
Hope this helps
John
Linear Mode
