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Discussion Starter #1
I purchased my DMax in the summer. Now that winter is here, I was wondering about how the two batteries work? Are they simply interconnected or is one used for certain loads and the other for other functions? If I want to park the truck for several weeks, do I need 2 float chargers?

I guess I should pick up a "Haynes" for the electrical diagrams...
 

LHN...We ARE the Joneses
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Wired in parallel, they're two halves of one large battery. Not two singles with different uses.

One float hooked to either will work, or a cig light/aux port plug-in with a solar panel to lay on the dash (if parked outside).
 

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Discussion Starter #3
Perfect.

Going south for a few weeks this winter (without the 5th wheel!) and the truck will be in the garage for that period.
 

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I purchased my DMax in the summer. Now that winter is here, I was wondering about how the two batteries work? Are they simply interconnected or is one used for certain loads and the other for other functions? If I want to park the truck for several weeks, do I need 2 float chargers?

I guess I should pick up a "Haynes" for the electrical diagrams...
Both - are connected to each other, both + are connected to each other. They are electrically 1 single 12V battery.
 

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If it's only for a few weeks I wouldn't even worry about it.

Of course a maintainer (as opposed conventional charge only device) isn't going to hurt.


There is a way to set them back to shipping mode and use even less power.

https://www.dieselplace.com/forum/attachments/76-speciality-forums/81-electrical/291242d1422668911-transport-mode-enable-_20150130_204806.jpg

Start engine .... and then turn key to start position sounds like a problem. I hope a few brave souls try this before I do.
 

LHN...We ARE the Joneses
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There's logic in the ecm to keep the starter from engaging when the engine is running.
 

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Hook have you seen the positive terminals on this new trucks? Spider web of wires.
 

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I see the bulleten is from 2014... Has anyone confirmed / used this on a L5P?
You made we curious enough to try.

Seems to works as advertised.


Start engine.
Activate flashers.
Foot on brake.
Key to 'crank' for 15 seconds.

'Transport mode on' message appears in DIC.

Battery icon on dash also shows in red. (Radio keeps playing...fan keeps running...)


Deactivates the same way.

DIC message 'Transport mode off'.
'Dismiss' button appears, battery icon turns off.
 

Diesel Junky
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So what is the point of transport mode


Sent from my SM-G973U using Tapatalk
 

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Reduce battery draw while in storage or in staging areas.
 

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Discussion Starter #16

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I would get out of the truck, close the door and not worry the batteries for even a month of sitting.
My spare 04 1500 (Old and Busted) sits for months at a time with an Interstate blem battery in it. Usually starts no problem. My 48 hp John Deere sits outside for months in the winter without running and starts fine.
 

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If you ever change batteries you have to, change both at same time. Your system is only as good as your weakest battery same goes for TV remote cant have 2 new ones and 1 bad one
 
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