E-350 Second Battery Question
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E-350 Second Battery Question
My 2004 E-350 15pass came with a second battery located under the sliding door where it is bolted in a box to the Frame rail. Does anyone know how that battery works? is it wired in parallel to the starting battery or does it run power to the van when the van is turned off?
Last week I had a dead starter battery that would not recover from re-charging and I had to buy a new one. I am trying to figure out if the second battery should have started the van, and if maybe I need to replace that battery as well.
someone told me that the second battery is a deep cycle type and runs the vans accessories after the van was shut off? Can someone point me in the right direction? HELP? HELP?
Last week I had a dead starter battery that would not recover from re-charging and I had to buy a new one. I am trying to figure out if the second battery should have started the van, and if maybe I need to replace that battery as well.
someone told me that the second battery is a deep cycle type and runs the vans accessories after the van was shut off? Can someone point me in the right direction? HELP? HELP?
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Originally Posted by Casey
I've looked at the wiring diagrams because I had the same thing on my van last week. The second battery is in parallel with the main battery.
I wanted to get this figured out because I was thinking of adding some accessories to the back of the van and wire them directly to the second battery, but I'm not sure if thats a good idea if the second battery is in parallel with the main battery?
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Originally Posted by Desert-Rat
Thats really odd then? why didn't my second battery start the Van? I wonder if the solinoid shut down the current so the second battery would not be drained?
I assume that both batteries are dead. One may be salvagable, but it is usually better to replace both at once. If one battery is bad it can quickly drain the second one.
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From: South TX
The factory option auxillery battery on the gas engines vans (diesels are different) are wired to provide isolated power to the trailer tow plug. They are not wired to assist the starting battery. With some modification, they could be.
The auxillery battery would be a good choice to power any accessories you add to your van that you don't want to draw down your start battery.
If you're not using your tow plug and have not connected any aftermarket loads to the second battery, then it's just there doing nothing.
The auxillery battery would be a good choice to power any accessories you add to your van that you don't want to draw down your start battery.
If you're not using your tow plug and have not connected any aftermarket loads to the second battery, then it's just there doing nothing.
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Ok, so it sounds like they are wired parallel so that when the main battery has been charged while driving, the second battery is then charged. And the second battery is there to run power only to the trailer accessory plug, which I only use to tow a quad trailer.
If this is the case, I should not need to replace that aux battery just because my main starting battey has gone bad.
hopefully this information is correct for a 2004 E350. I am going to see if I can get an All Data print out on this and verify with the dealer before I start feeding power to the back of the van from the aux battery. But I think that the aux battery would be pefect to run a dvd player, spare power ports and play station for the kids in the back of the van!
If this is the case, I should not need to replace that aux battery just because my main starting battey has gone bad.
hopefully this information is correct for a 2004 E350. I am going to see if I can get an All Data print out on this and verify with the dealer before I start feeding power to the back of the van from the aux battery. But I think that the aux battery would be pefect to run a dvd player, spare power ports and play station for the kids in the back of the van!
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That second battery sure is nice. I have a 2004 E350 and I swapped out the clutch fan with a big Flex-A-Lite electric puller, that's tapped into the aux battery at the power distribution box under the hood. All other aftermarket accessories I have are also powered off of this box.
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Originally Posted by carrfamilynj
That second battery sure is nice. I have a 2004 E350 and I swapped out the clutch fan with a big Flex-A-Lite electric puller, that's tapped into the aux battery at the power distribution box under the hood. All other aftermarket accessories I have are also powered off of this box.
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Down loaded information from a friends All Data software. Confirms that the second battery on gas engines is for the trailer plug. and that it is in fact a deep cycle battery. However it says that it supplies power to the trailer plug when the vehicle is running? So where do I tap in to get constant power ONLY from the second battery? At the battery post or the distribution box?
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Down loaded information from a friends All Data software. Confirms that the second battery on gas engines is for the trailer plug. and that it is in fact a deep cycle battery. However it says that it supplies power to the trailer plug when the vehicle is running? So where do I tap in to get constant power ONLY from the second battery? At the battery post or the distribution box?
I have yet to hook up anything to mine as well other than from Factory I had them install the auxiliary power switches. From the back of those I assume I should be able to hook up auxiliary items. I have yet to pull the panel out as I don't want to break any tabs. I'm sure there are other videos on YouTube showing how to.
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Fleet Owner
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From: Reynoldsburg, Ohio
Did you not notice this thread has been dormant for over 2 years now, that the member you quoted originally replied in Oct of 2006?
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