Another stupid newbie question. It looks like I'm going to acquire a used Hawk trailer. It's been sitting since last fall. I'm a little concerned about the breakaway battery. I have no idea if it still has a charge. While thinking about this, I realized I don't know even know how the breakaway battery is charged. Does it pull from the truck's electrical system? Require a trickle charger? Both? The mechanical parts of the trailer look like they're in reasonable shape; they'll at least survive the trip home. I'll obviously have someone competent look it over before I load any horses in it.
Posted 2006-04-09 7:42 PM (#40153 - in reply to #40132) Subject: RE: Explain brake batteries
Expert
Posts: 2689
Originally written by carp on 2006-04-08 11:33 PM
Another stupid newbie question. It looks like I'm going to acquire a used Hawk trailer. It's been sitting since last fall. I'm a little concerned about the breakaway battery. I have no idea if it still has a charge. While thinking about this, I realized I don't know even know how the breakaway battery is charged. Does it pull from the truck's electrical system? Require a trickle charger? Both? The mechanical parts of the trailer look like they're in reasonable shape; they'll at least survive the trip home. I'll obviously have someone competent look it over before I load any horses in it.
Hi and Welcome to the Forum.
Sorry if it seems like we're ignoring you.
Yes, they charge from the tow vehicle - via either the +12 or the +AUX wire. If the tow vehicle is a FORD it will probably only charge while the ignition key is in the run position, though the engine doesn't have to be actually running. GM and (I think) Dodge have power to that pin at all times.
IF ...I know, there are lots of IFs... the battery was in fair shape last fall I would GUESS as follows: By the time you hook it up to your tow vehicle and get to your horses (over 1/2 hour ?) that battery will most likely be charged well enough to do it's job (although we all hope it will never have to).
There are other threads that deal with checking the breakaway mechanism and battery state of charge. Basically if you have your trailer hooked up to the tow vehicle you can test it on a gentle slope by parking, disconnecting the trailer plug and pulling the breakaway pin, then get in the tow vehicle and see if it will roll in neutral with the parking brake released. If not put it back in park and/or apply the parking brake, replace the breakaway pin, reconnect the trailer wiring and verify that the rig will roll when the brakes are released. This isn't very quantified, but it should give you some idea of whether everything is THERE.
Back to the IF;
Trailer breakaway batteries have a different life to car/truck starter batteries. They rarely get called upon to supply current, they spend their active life at the end of a long skinny wire that might be 50ft from the charging source and in some cases are left for many months of "off season". I don't know what a fair life expectancy is, but they're relatively cheap, so if the trailer is much more than 5 years old it might be a good idea to replace it anyway.
Posted 2006-04-09 7:49 PM (#40155 - in reply to #40153) Subject: RE: Explain brake batteries
Veteran
Posts: 202 Location: North Texas
My trailer is not a Hawk. Neither it or the trailer I had before charges from the tow vehicle. It must be periodically removed and charged with a trickle charger. It seems to last about a year before needing to be recharged.
I keep thinking that I will wire it so that it does but I never seem to get around to it.
Posted 2006-04-10 7:53 AM (#40174 - in reply to #40155) Subject: RE: Explain brake batteries
Extreme Veteran
Posts: 366 Location: Albany, Oregon
Originally written by arroyoseccofarm on 2006-04-09 5:49 PM
My trailer is not a Hawk. Neither it or the trailer I had before charges from the tow vehicle. It must be periodically removed and charged with a trickle charger. It seems to last about a year before needing to be recharged.
I keep thinking that I will wire it so that it does but I never seem to get around to it.
Same here....you have to buy an add on charger that will charge the gell cell breakaway battery. Or buy the system with the charger installed. Most trailer don't have that option installed. I charge mine once a year or so with a trickel charger....I found these add on types....http://www.tekonsha.com/tbsabatcharg.html
Posted 2006-04-16 8:31 PM (#40521 - in reply to #40132) Subject: RE: Explain brake batteries
Member
Posts: 5
Location: New England
Thanks everyone for the helpful advice. The trailer is indeed going to come home with me. Good news-the trailer is still under warranty. Bad news-I'm probably not going to be able to do any serious testing or troubleshooting where it's currently parked. It's leaving with me if the brake lights work. Good news-someone I know nearby has agreed to let me park the trailer in her driveway temporarily. I can leave it there while I go over the electrical system thoroughly.
Posted 2006-04-17 12:53 PM (#40549 - in reply to #40132) Subject: RE: Explain brake batteries
Expert
Posts: 2689
EACH of my trailers charges from the tow vehicle.
EACH of them have status lights on the breakaway switch box, it shows green "charging" as soon as the trailer is connected.
EACH trailers and each tow vehicle (Chev & Dodge) has a 7 pin connector.
The breakaway switches are "Hoppy" brand, which is probably what determines the wiring schematic and thereby the "charging when connected" policy.
Explain brake batteries
