Is the battery supposed to be charged by the tow vehicle while the tow vehicle is on? I am finding that the battery is not being charged by the tow vehicle. My last fifth wheeler charged the battery while the tow vehicle was running. I assume that the vehicle alternator was also charging the trailer battery while the engine is running. So, how is the trailer battery being charged?
SOLVED: Coach battery not getting charge from truck
- Thread starter CCWREW
- Start date
Re: ATF: Bighorn - Battery Chaarger
Sometimes, the truck maker does not have a fuse in the fuse holder on the line that charges the coach battery - or that fuse is blown. If you have a volt meter, using the DC mode, check on pin 4 of your truck's 7-wire receptacle while the truck is on.
So that's the read lead of the meter to pin 4 and the black lead to pin 1 (ground). Here's a link to a diagram of the pinout on the Wiki.
If you don't have DC power between pins 4 and 1, then you need to resolve it with your truck. If you do have power there, then you'll have to start troubleshooting it at the RV. Others will chime in here to help you with that.
Jim
Sometimes, the truck maker does not have a fuse in the fuse holder on the line that charges the coach battery - or that fuse is blown. If you have a volt meter, using the DC mode, check on pin 4 of your truck's 7-wire receptacle while the truck is on.
So that's the read lead of the meter to pin 4 and the black lead to pin 1 (ground). Here's a link to a diagram of the pinout on the Wiki.
If you don't have DC power between pins 4 and 1, then you need to resolve it with your truck. If you do have power there, then you'll have to start troubleshooting it at the RV. Others will chime in here to help you with that.
Jim
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wdk450
Well-known member
Re: ATF: Bighorn - Battery Chaarger
I just found this was happening with my rig last month, and I didn't realize it (as most people won't). It was due to a blown 30 amp fuse in the truck fuse bank. I'm thinking that a LED indicator should be installed on the truck's trailer connector to let you know if the circuit is working. Of course, you need to check with the truck engine running and the trailer disconnected (so that the trailer's battery won't provide the power for the LED).
I just found this was happening with my rig last month, and I didn't realize it (as most people won't). It was due to a blown 30 amp fuse in the truck fuse bank. I'm thinking that a LED indicator should be installed on the truck's trailer connector to let you know if the circuit is working. Of course, you need to check with the truck engine running and the trailer disconnected (so that the trailer's battery won't provide the power for the LED).
brianharrison
Well-known member
Re: ATF: Bighorn - Battery Chaarger
I bought one of these 7 pin testers to help with 7-pin tow vehicle circuit issues. 7 Pin circuit tester - 10 bucks.
Brian
I bought one of these 7 pin testers to help with 7-pin tow vehicle circuit issues. 7 Pin circuit tester - 10 bucks.
Brian
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Re: ATF: Bighorn - Battery Chaarger
After two previous trailers, I did find, at your suggestion, that the fuse was indeed blown on the truck fuse bank. You mentioned a 30 amp fuse while mine is only a twenty amp. I have a 2500 cummins 5.9 2005 RAM truck. Should I put a 30 amp back instead of a 20 amp?
After two previous trailers, I did find, at your suggestion, that the fuse was indeed blown on the truck fuse bank. You mentioned a 30 amp fuse while mine is only a twenty amp. I have a 2500 cummins 5.9 2005 RAM truck. Should I put a 30 amp back instead of a 20 amp?
wdk450
Well-known member
Re: ATF: Bighorn - Battery Chaarger
Maybe it WAS a 20 amp. I know in my old motorhome it was a 60 amp circuit breaker. That makes me wonder if 20 amps does much, or gets blown often by my 4 battery bank.
I put in whatever the truck fusepanel top listed as correct.
BTW, I found self resetting circuit breakers that fit into the fuseholder socket at Autozone. They are a lot longer than the standard fuse, but looked like they would fit under the Dodge's fuse cover.
Maybe it WAS a 20 amp. I know in my old motorhome it was a 60 amp circuit breaker. That makes me wonder if 20 amps does much, or gets blown often by my 4 battery bank.
I put in whatever the truck fusepanel top listed as correct.
BTW, I found self resetting circuit breakers that fit into the fuseholder socket at Autozone. They are a lot longer than the standard fuse, but looked like they would fit under the Dodge's fuse cover.
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Re: ATF: Bighorn - Battery Chaarger
We had the same problem. You didn't list what vehicle you have but Fords don't generally come with a fuse or relay installed even if the tow package is factory. The two components are in a plastic bag somewhere in the vehicle. My buddy called me with the problem. He took it to the camper place and the dealer. I told him about the relay and fuse and two weeks later he found them in the truck. Now what sense does it make to get a TV with the tow package and not have the relay and fuse installed. Here's the probably reason as explained by the Ford service writer. When they are installed you have a hot 12-V wire going from the front to the back. If you were in an accident it's very possible that that wire would/could short and maybe start a fire if some fuel were around. SSSSSoooooo Ford does not want to take the chance of that happening until you buy the truck and use it to tow your camper. My dealer told me that every truck comes from the factory with those two parts in a plastic bag somewhere in the truck. Remember the story, "What do you have if there are 10,000 lawyers at the bottom of the ocean? A good start.
JMTCW
TeJay
We had the same problem. You didn't list what vehicle you have but Fords don't generally come with a fuse or relay installed even if the tow package is factory. The two components are in a plastic bag somewhere in the vehicle. My buddy called me with the problem. He took it to the camper place and the dealer. I told him about the relay and fuse and two weeks later he found them in the truck. Now what sense does it make to get a TV with the tow package and not have the relay and fuse installed. Here's the probably reason as explained by the Ford service writer. When they are installed you have a hot 12-V wire going from the front to the back. If you were in an accident it's very possible that that wire would/could short and maybe start a fire if some fuel were around. SSSSSoooooo Ford does not want to take the chance of that happening until you buy the truck and use it to tow your camper. My dealer told me that every truck comes from the factory with those two parts in a plastic bag somewhere in the truck. Remember the story, "What do you have if there are 10,000 lawyers at the bottom of the ocean? A good start.
JMTCW
TeJay
rick_debbie_gallant
Well-known member
What about running a heavier gauge wire back to the 7 way, fused of coarse. Then put in a heaver fuse. Or hook up a solar charger to the front of the pin box and run those cables to the battery. You could even mount to the roof.
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traveler44
Well-known member
I had to add a relay in the under the hood fuse box on my Ford. It is a black cube with a couple of spade connectors that plug right in. Tom
JohnDar
Prolifically Gabby Member
I think you're right on the 40A, Bob. Either my GMC came with it or the dealer where I got the rig put it in while they installed the hitch, but no problems.
happykraut
Well-known member
Re: ATF: Bighorn - Battery Chaarger
It is NEVER a good idea to overfuse a circuit. The fuse is there to protect the circuitry AND the wiring. Too large a fuse and the wires become your fuse. Not a good idea.
happykraut
Well-known member
Re: ATF: Bighorn - Battery Chaarger
Anyone have any experience using one of these testers? Seems like a good thing to have in your toolbox.
brianharrison
Well-known member
Re: ATF: Bighorn - Battery Chaarger
Yup - I find it handy. It took a little reading of the instructions to figure out the LED pin out lights (ie what lights up when the circuits are all good, when one circuit is pooped, etc). If you want to go all out and spend $250 to $300, you can purchase one of these cool units to test the trailer wiring --> http://www.etrailer.com/comparison.aspx?pc=8010&pc2=HM50928
I carry the simple tow vehicle wiring tester in my toolbox in the trailer, and have used it a couple of times when fellow campers arrived in the campsite with NFG lights, brakes, charging circuits etc. A couple of adult beverages and the tester, and we have great conversations and meeting new people.....
Brian
Yup - I find it handy. It took a little reading of the instructions to figure out the LED pin out lights (ie what lights up when the circuits are all good, when one circuit is pooped, etc). If you want to go all out and spend $250 to $300, you can purchase one of these cool units to test the trailer wiring --> http://www.etrailer.com/comparison.aspx?pc=8010&pc2=HM50928
I carry the simple tow vehicle wiring tester in my toolbox in the trailer, and have used it a couple of times when fellow campers arrived in the campsite with NFG lights, brakes, charging circuits etc. A couple of adult beverages and the tester, and we have great conversations and meeting new people.....
Brian
