Can anyone help out on this issue:
I understand that when I hook up my A/S to my truck, the battery in the A/S should be charging from the truck alternator, correct?
If so, how can I tell when this is happening?
I usually hear a buzzing/humming sound from the Univolt when its hooked up to shore power, this I assume is telling me the system is working. I dont hear this sound when its hooked up to the tow vehicle. Any suggestions?????
Thanks for your help
Alex
Alex,
When you are connected to the tow vehicle, you are using the same system that keeps your tow vehicle battery charged. The Humming you hear when you are connected to 110 is the sound of the old Univolt system. You will only hear the hum when 110 volt power is connected.
Ray,
Thanks for your reply!!
I am still a bit confused on this issue. Is their a way of telling if my A/S battery is being properly charged from my tow vehicle when in tow? Which wire from the 7 pin wiring harness is the one used to charge the battery, if their is one?
Alex,
If you are wired to A/S specs, you could use the color code from A/S. Probally not the case, so just use a simple tester to locate which wire is "hot" when everything is turned off in your tow vehicle. You should not try to charge your battery completely in this manner. After reading the links I suggested, you will see why. A much better choice, I think, would be to use a deep cyle automotive charger to bring it to full charge before going on the road.
Ray
If I remember correctly, the center pin is the one that charges.
__________________ Craig
AIR #0078
'01 2500hd ext. cab, 8.1 litre gas, 5 sp. Allison auto
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The diagram points to the blue wire being the charge wire - - remember that your connector has likely been rewired to the more modern standard so the location by terminal will likely be different.
The degree to which your tow vehicle will be able to replenish the charge in the trailer batteries is dependent upon the size of the wire run from the tow vehicle source back to the connector plug (plus the size of the wire carrying the charge from the trailer connector back to the battery - - that can be quite a distance if your battery happens to be in the rear compartment as it is in my '64 Overlander) as well as capacity of the tow vehicle charging system to handle additional load. I notice very minimal charging when towing with my '75 Cadillac, and my Suburban only does a little better - - but I am also running my refrigerator on 12-volt while traveling.
Kevin
__________________
Kevin D. Allen WBCCI (Lifetime Member)/VAC/Free Wheelers #6359 AIR #827
1964 Overlander International/1999 GMC K2500 Suburban (7400 VORTEC/4.11 Differentials)
1978 Argosy Minuet 6.0 Metre/1975 Cadillac Eldorado Convertible (8.2 Liter V8/2.70 Final Drive)
I too have pondered the same question about the charge line. Here are a few of my thoughts.
Overlander gave you the correct link on the wiring for the connector.
To see if it is charging try the following.
You can watch you vehicle ammeter and have someone hook up the trailer connector, it should show a jump if it is chargeing {motor must be running}.
You could turn on some lights in the trailer and see if they get brighter when the running vehicle is hooked up.
I for one am eventually going to hook up an ammeter on the charge line and place a permenant meter in the cab of the truck. Should work fine by using a 100amp shunt.
I don't know about the rest of you folks, but when I hook up my tow vehicle to my trailer, the voltmeter in the trailer goes up. There is no reason why you couldn't hook up an automotive type voltmeter in your trailer, with a momentary-contact switch, and check the voltage. Push the button, and anything over about 12.6 volts means it is being charged. This assumes your battery was up to begin with, but you get the idea.
Terry
This looked like a good spot to ask this question.
My 02 Safari only has one battery. On rare occasions it would be nice to be able to connect to a second battery. I had one of those half baked ideas that often do not work the way I think they should.
Could you take second battery and connect it to the +/- on a female 7 pin connector, then when one of those occasions occurred were you needed a second battery, just connect the 7 pin pig tail to the female end that is connected to the battery?
If you reconnected back to 110 electricity would the system also charge back through the pig tail and adaptor to the second battery?
Originally posted by Ruebel This looked like a good spot to ask this question.
My 02 Safari only has one battery. On rare occasions it would be nice to be able to connect to a second battery. I had one of those half baked ideas that often do not work the way I think they should.
Could you take second battery and connect it to the +/- on a female 7 pin connector, then when one of those occasions occurred were you needed a second battery, just connect the 7 pin pig tail to the female end that is connected to the battery?
If you reconnected back to 110 electricity would the system also charge back through the pig tail and adaptor to the second battery?
Larry Ruebel
Bismarck ND
In theory, it would work, I would want to put a fuse in the line to protect your wiring, however. Probably a 20 amp fuse would suffice, I can't imagine the lights in your coach drawing more than that, and it would keep your wiring harness from doing its own little version of Chernobyl. Put it in the part that would go from your trailer harness into your extra battery.
Terry
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