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Honda Accord 12v access in cabin with switch off

2012 Honda Accord EXL
I use my car so seldom and for such short trips that my battery does not fully charge. It is ok for a while after a 40 minute trip but I often use my jump starter to start it, especially on cold days. I bought a solar trickle charger. I would like to finally find a use for the moon roof and put the charger up there and run wires (with a switch as the charger instructions say not to run with it connected) to the battery. I would rather not penetrate the fire wall. I would like to know just where I can connect the positive line in the cabin. I am assuming the ground would be easier to do but am not entirely sure. I am rather chubby and have a bad back and would REALLY rather not crawl under my dash for a long hunt for an unswitched +12 volt line. Can anyone give me some direction here?

Seriously, just how much trouble is it to just raise the hood and disconnect the Solar Charger . Why make something more difficult then it needs to be.

I don’t think Hondas do but check to see if the cigarette light is hot all the time. My Chevy is but I think my Honda was not. If it is, buy a male plug and wire it to the solar charger and plug it in. Remove when you drive away.

If this thing in going on the sunroof is it INside or outside? Outside would get more solar gain. Inside would be easier to wire

On Chrysler minivans you can change the position of a fuse under the hood to power or depower one of the “lighter” sockets.

If that’s not an option and you want to plug into the lighter socket, a car stereo shop can probably do a small wiring job under the dash quickly and not charge very much.

Thanks for the responses. I do not want to be leaving my charger out side of the car. I want to finally use the moon roof for something;) it would be simple and neet if I can find an easily accessible hot line. My cars DC recepticle is not powered if the ignition switch is off, with it on (should I really want to leave my keys in the car) I would think the extra load would take enough current to negate the chargers efforts. Again I would like to know just where I can easily access a hot line. I do not want to throw out my back crawling under the dash for a hunting expedition.

shanonia that is an interesting idea I will see if that might apply to my Accord.

That’s the ticket if OP isn’t technically savvy.

I have a 10 watt solar panel that sits on the dashboard.
A simpler wiring path than going up to the moonroof.
Brings the battery up to ~13.5V every sunny day, even though I’m now driving ~2 miles a week.

I used a voltmeter and insulation piercing probe to find an always “hot” wire under the dash.
Then I added a connector (Anderson PowerPole) under there to easily disconnect the panel.
If there’s a fuse panel under the dash you can get a tapping device that piggy backs a fuse and brings out a wire.

OK assuming I get a lead on just what to connect to from a Honda person it sounds like the tapping device would be a possible option to actually do that. Can you give a lead on that? In a search vocabulary is important here.
I see Anderson PowerPole makes a bunch of stuff. Just what to look for would still be a problem. Maybe I should request a digikey catalog( have not seen one in many years!)

Again the moon roof seems like a perfect home for the charger and an internal connection to power is what I seek.

Here’s an example of the PowerPoles I use:
There are plenty of other connectors out there to choose from.
I just happen to have these on hand and use them lots.

Here’s an example of a fuse tap:
Just make sure you get the right size.
Might be available at a parts store where you can eyeball it.

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Now that is what I need, I just need to id a fuse, I believe that should be very doable :smiley:
Now if I had just waited 5 minutes before putting in an amazon order iI could have added it :laughing:

I guess I need to find something else to spend on …

There are usually empty sockets in the fuse box, one might be always live. You can also buy an adapter to tap into an always live fuse.

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What might the O/P of the fuse goto? Hopefully nothing.
IPS I managed to redo my Amazon order and get the adapter!!

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I had another thought last night, when I open my door power is given to a couple of interior lights and other items. How do I know if a live fuse will still be live with the door closed? I guess I can figure it out. Nice day to do a bit of work outside even if a bit cold still. Thanks again for all your helpful suggestions!
Stay Safe

I’ve had to do this sort of thing oh… a few thousand times? Depending on the load of the items that need to be run usually dictates the lengths taken to supply the power, the fuse and the wire gauge. Fuse taps arent my fav as they will inevitably “spread” the terminal connector in the fuse panel and forever be loose after that until you re crimp that connector…so fuse taps are best left unused and if they are used…to leave them in place and never remove them. Never use Scotch Locks or Vampire Connectors as I’ve always called them…they are just best left unused, period.

I think nothing of running my own power line straight from the battery itself…adding an inline fuse of course and you are in business. You can select any type of fuse holder / fuse under the sun…just pick one that you are comfortable with and run with it.

Nothing exotic…just a power line from the batt with a fuse…run correctly thru the vehicle using wire ties and grommets if going through the firewall or metal etc…Shrink wrap and solder if needed are never a bad thing. Its pretty straight forward. Then again, I always forget that I may be advising someone without 30+ years of tools and connectors and wire etc …tools are required in my example, so I apologize, but not really because that is how it is done correctly.


I just tried to find a ‘hot’ fuse on my car and what a piss poor place to put the fuse box!! I was at it for nearly an hour and w/o taking out the fuse I was not able to get my pin probe to connect to any thing. (See I do have some tools!) took me a while to confirm I had a good ground to test with, the big green wire I was thinking was a ground did not seem to be or I was just not putting my probe in enough. With the position of the panel I was not able to see it very well even w/ 2 flash lights going. The firewall idea is sounding better and better.
What should I know about going through the firewall? Am I going to have to drill a hole? I might as well put a ground line through as well an fuse both.
Now I am gonna go find a heating pad for my back :expressionless:

All fuses have those test tabs available for you to probe or test them… If your tool cannot get to these tabs due to being too blunt or what have you… You can tape a sewing needle or safety pin…or wire to your probe so that it will be able to access the fuse test points.

As far as going thru the firewall? Theres nothing like hitching a ride through…I mean why make a hole when some one or thing already made one for you? Look on your firewall for anything going through it…it will usually have a grommet already…hitch a ride…

Some places people favor? The area where your steering column goes through the firewall is common as that area usually has plastic or rubber filler to close up the hole… a lot of people go through that… I prefer smaller openings like say where a cable went through or even dummy plugs in the firewall made of hard plastic or rubber.

Long ago I made a bunch of “grommet drills” out of the hollow bottom tube of telescoping antennae… Put into a power drill and you have a nice safe, semi blunt, not sharp grommet drill. I still have a bunch of those floating around…helps to put some cuts into the cutting or drill end but not always needed…they usually will take a perfect plug of rubber or plastic right out of what you drill thru…and you have to pop it out of the hollow tube when finished. The best part is once you are thru the material…just unhook the “drill” from your drill chuck and it acts like a fish or conduit to push your new wire thru…great tool… Another idea I should patent…


I did a google on fuse test tabs, I just could not see them. Knowing they are there I may give that another go as I have the tap s on order. I was considering taking the bottom part of the dash off to be able to see what I am doing there, but with this info I will have a better shot w/o risking damage to the retaining clips.
I will take a look at my firewall as well. I also have a n old antenna around .

Many thanks

The tabs on the fuse are on either side of where the fuse amp rating is… without a picture it would look something like this:

                                         - 15 -       

Looking down upon a 15 amp fuse for instance…even mini fuses have them… they are small…but they are there and are bare metal…slightly recessed to avoid arcing on anything etc…

That isn’t necessary. There are lots of nuts and bolts in the dashboard/firewall area that are good grounds.


Yup saw that clearly on the video :slight_smile:
Will revisit tommorow given clear weather.