Help getting wiring through the firewall?

Guy

Has gone over to the oily side...
Club Member
Evening all, bought an under seat sub for my car but can I find a bung in the firewall?! Tried to get the glove box out with no luck and the whole firewall seems to hidden behind a moulded on slab of PU foam.

I know I'm meant to be pretty hot on K12 but this has got me beaten :down:.
 

gtsnissanb

Official MSC Trader
Just find a permanent live on the fuse board and run a fuse tap if your struggling, That's how I wire permanent lives as allot of bulk heads are hard to get through! I've got a load of fuse taps here you can have one if you need there usually £7 a pair on eBay! Give me a shout mate I do loads of vehicle electric work in my line of work so have loads of connectors and scotch locks and such
 
OP
OP
Guy

Guy

Has gone over to the oily side...
Club Member
Just had a look at what a 'fuse tap' actually is on eBay and can only say: You're a genius sir (Y). The sub's only 100 real watts max so a 20A mini tap will do the job just fine.
 

gtsnissanb

Official MSC Trader
Just had a look at what a 'fuse tap' actually is on eBay and can only say: You're a genius sir (Y). The sub's only 100 real watts max so a 20A mini tap will do the job just fine.

Pm me which you need mate mini fuse or regular and your address and I'll stick one in the post for you if you want
 

Dragonmaster_uk

K12 NUTTER
If you did want to use a proper 12v feed from the battery there is a useful grommit right up behind the drivers side dash that i've used for mine can get pics later if you want
 
I've had problems getting stuff to go thru my firewall too.
I just turned off my antivirus! :laugh:

What about running a fused live from the cigar lighter?
 
OP
OP
Guy

Guy

Has gone over to the oily side...
Club Member
I've had problems getting stuff to go thru my firewall too. I just turned off my antivirus!

Lol, you wally :laugh:.

Cheers Pete, I've not had a good look at the drivers side yet - a pic would be awesome mate. gtsnissanb, that's an extremely kind offer squire I'll take you up on if I have no luck with finding a grommet (Y).
 
To get the power through to my sub, I took the top of the dash off, and there's a rubber bung in the firewall behind the battery. I simply popped the bottom half of it off, and fed the wire through - it comes through a gap in the foam, and out behind the dashboard, from where I tucked it under the carpet.

I initially tried to stab a hole in the bung, but the cable just wouldn't feed through - and you don't have any decent access to the inside to grab at it, hence I just tucked it under the bottom of the bung.

Alternatively, if you're brave, you could remove the dash, and drill from the engine bay into the car, and seal it all with silicone once it's done. Easy if you're careful - worked fine in my pug.
 
:laugh:
Ok, fingers begun typing before brain was up to 4th gear.

What we used to do when this problem arose when I worked in dealerships was to take out something easy, the glovebox or kick panel etc. and gently coax a bit of welding wire with a hook bent in the end thru. Jiggle it about a bit then look to see where is comes out! Its a bit caveman but it works. The hook on the end helps you run wire back thru. Just make sure you have not popped out any big grommets and your wire isnt going to chafe.

If you follow the loom back to where it passes thru the firewall you will probably find a big grommet taped up so it would be tricky to get a thick wire thru it without pulling it apart.
 
OP
OP
Guy

Guy

Has gone over to the oily side...
Club Member
I took the dash off and had a good look down the firewall. The only bung I saw was a huge rubber surrounding a FAT bunch of cables. Didn't feel like there was any spare room around the wires either where they went through :grinning:.
 
PICS (sorry for the grubby state of my engine...):

enginebay.jpg


enginebay3.jpg


enginebay2.jpg
 

gtsnissanb

Official MSC Trader
runnig a sub from fuse or a lighter? really?*geek*

I'd imagine he means the 12v on the lighter the wire on that would be far too thin I'm afraid plus not all lighters are permanent lives
Hence why I use fuse taps you just find a permanent live on the fuse board and stick in the tap easy then it's got it's own fuse running from a good 12v, I am 100% and then some certain that it is fine for a sub! As that's how I wire caravan charging and rear light power systems on twin electric setups

Also all the faffing about getting a live running through the engine bay pass hot and moving components then making sure nothing is catching rubbing it is frankly a waste of time when you can just open the in car fuse box locate the live plug the wire in and it's done

No big ugly candy red chavvy wires, no risk of water getting through the grommet into the footwell (providing Nissan sealed it well enough:eek: ) no rusty live cable, works especially well if you doing a wire tuck
 
Hi fella’s
I know it’s a bit late, but I’m in the middle of installing an under seat sub.
I’ve managed to find a gromit that leads straight thru the firewall, the only thing I had to do was remove the glove box then probe around the insulation and it’s to the left of the big bunch of cables, you can see where the insulation is sort of joined and it’s thru there! I’ll attach a couple of pics
 

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Mika The Finn

Site Supporter
There it is ;)
From there => -06 Micra 160 SR of Mika The Finn
For Pioneer TS-WX120A Active Subwoofer 150 Watt I routed power cable trough firewall grommet covered opening to battery, of course through fuse.

Location of opening is some what difficult to see under the hood/bonnet. Standing front of the vehicle it's located on left behind strut tower.

Firewall%20hole%20engine%20compartment_1_zpsqu8tbpvs.jpg




Firewall%20hole%20engine%20compartment_2_zpsw1dn5jab.jpg



From inside of vehicle, on left side of firewall. You have to remove glove box to gain access to opening.

Firewall%20hole%20interior%20left_1_zpscq2efuj5.jpg




Car's have 4 windows, vehicles have more... ;)
 
That’s it bud, obviously yours is on the opposite side to where mine is, but I’ve got my sub working now and hidden under the passenger seat 👍
 
Good luck! :)

Pic of passenger seat storage.

EdTOJTLXYAIg4ge
Thanks, i misquoted the wrong post, meant to quote the one about wire through firewall, perfect spot easy access, im also putting it under the seat with box removed, 1 question, where did you run the ground wire, i was thinking about using 1 the bolts from the seat, or perhaps the seatbelt 1, what u recommend, been waiting for some wiring adapters but will install tommorow or friday, im slightly worried about ill get issues with the NATS after removing the negativ wire from battery doe :/
 

Mika The Finn

Site Supporter
Thanks, i misquoted the wrong post, meant to quote the one about wire through firewall, perfect spot easy access, im also putting it under the seat with box removed, 1 question, where did you run the ground wire, i was thinking about using 1 the bolts from the seat, or perhaps the seatbelt 1, what u recommend, been waiting for some wiring adapters but will install tommorow or friday, im slightly worried about ill get issues with the NATS after removing the negativ wire from battery doe :/
I put my ground wire under rear seat bracket/bolt. Nothing sliding over the bolts like in front seat bolts.
Measured 3 times that everything is fine, never removed negative battery cable!;)
 
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