When I have my truck hooked up to our horse trailer, the batteries aren't getting charged. I checked the wires on the truck and when it is running I am getting 13.6 volts going to the trailer(center wire on the plug). I have a 2000 Featherlite trailer. I have checked the fuses in the trailer and none of them are blown. When I have the trailer plugged in to 110 volt or the generator running, the batteries are charging fine. I need your help. Thanks.
Posted 2005-06-19 2:39 PM (#26778 - in reply to #26776) Subject: RE: Truck not charging trailer batteries
Expert
Posts: 2689
Originally written by ddkrueger on 2005-06-19 12:23 PM
When I have my truck hooked up to our horse trailer, the batteries aren't getting charged. I checked the wires on the truck and when it is running I am getting 13.6 volts going to the trailer(center wire on the plug). I have a 2000 Featherlite trailer. I have checked the fuses in the trailer and none of them are blown. When I have the trailer plugged in to 110 volt or the generator running, the batteries are charging fine. I need your help. Thanks.
If you're measuring it with the trailer unplugged then the 13.6 is the OPEN CIRCUIT voltage from your truck. I agree, that isn't enough to charge a 12 volt battery. When loaded it is probably dropping to under 13, even worse. As you say, the batteries charge fine from your generator or shore power, so Golly-Gee, this is a truck problem. Something somewhere in your truck needs a fixin'. When you have volts (though not enough) but don't get amps, you probably have RESISTANCE !
I'd be hunting around for dirty or corroded connections somewhere between the truck batts and that center pin.
BTW, if this is a F*rd the center pin should be cold when the ign switch is off, this also means that there is an extra contact to deal with.
Posted 2005-06-22 12:26 PM (#26932 - in reply to #26776) Subject: RE: Truck not charging trailer batteries
Elite Veteran
Posts: 800 Location: Tenn/Ala.
Another thought- If Lonnie's out there he might can help. But if your trailer is a living quarters from Featherlite Interiors, I have seen more than one come through our shop that was not built with a "charge line". Ie there was no connection between the LQs 12V circuit, and the accessory circuit in the truck. If that is the case with yours, it is easy enough to run one from the neck to the batteries. One way to test for its presence, is that with LQ plugged up & charging, test the center pin of the 6 pin trailer plug for current between it & the ground (ground is the bigger one). Current there shows a connection to the converter/battery circuit. No current- no charge line.
Posted 2005-07-01 9:23 AM (#27470 - in reply to #26776) Subject: RE: Truck not charging trailer batteries
Member
Posts: 6
Location: Outside Dallas, Texas
How do you know the batteries aren't getting charged? Are they dead when you go to use them at the end of the day, or did you actually measure no current flow at the batteries? The batteries may be charging fine but may not be able to hold the charge if their sulfated or similar. If they're a few years old they may be the problem and not the truck. Yank a battery and take it down to the local parts house that has a battery load tester. They'll put a load on it and see what the voltage does even if its fully charged. I'll bet its the batteries.
Truck not charging trailer batteries
