D-40 Running wires through firewall. What path?

I need to run a wire through the firewall to a light duty switch on dash to operate the big relay (not those little,often troublesome mini black relays) which incorporates a fuse,to provide power to my two driving lights,probably Ciebe's. The Nissan factory has done a top job with the engine compartment, so much so that I have yet to find a way to get my figure 8 cable through into the cabin without drilling. When pulling cables through places where there are live wires, I find that non conductive larger 'zip' ties are great, using the eye to attach the copper wire. Helpl please guys.

Surely there must be a way through the collection of wires near the steer column but where does it come out?

there is a large rubber grommet surrounding a heap of wires going thru the firewall just above the accelerator pedal, you can very carefully pierce a hole in the side of this grommet with an oring pick or alike but be really carefull not to damage any of the wiring, this could be devestating! i ran shu-roo wiring thru here on my d40. another way through is into the door jam and through the inner guard, i've seen it done with uhf antenna wiring but wouldn't recommend it. lastly, i'm pretty sure there are a couple of rubber plugs in the front of the lower left floorwell which can be removed but need to be really well sealed otherwise you will take on water. i have used this method for uhf antenna cable on a new patrol and excessively sealed it with sikaflex. i avoid drilling holes whenever possible. good luck.

Thanks FH1 I will check it out further. I rightly so get a bit nervous with Black Boxes and Air Bags. Never had to deal with tech like this in our Diahatsu etc.

Hi Rocky One, if u look under the dash and trace the bonnet catch cable, you will see a rubber grommet the size of a ten cent piece, ive run several wires through this grommet with great success and u can cable tie it to the bonnet catch cable and it looks really neat and proffesional..........hope this helps.

good call mp3

For anyone coming across this thread in the future there is a nice convenient hole in the firewall on the passenger side of the vehicle that comes out in the cabin just above the left kick panel.

I used this hole to run a direct feed from the reversing light fuse block (for want of a better word) straight into the cabin to power the camera screen when reverse is selected. People have suggested previous that the reversing light cable actually goes under the seat in Nav's but having not found it after 2 mins of looking I chose this path because it seemed so easy and coming off the fuse direct means I know I got the right wire.

I also found enough room in this hole to run the CB aerial lead (with no connectors on it) and the cable for my second battery since I choose the in cabin route in preference to the chassis rail route for the battery cable.

What a fantastic thread! I am just about to install a UHF and now know where to run the aerial and wiring.

I'm curious, since there are a number of pics of Nav's playing submarines in the gallery ...

How do you keep the water from getting into the cabin if you're poking holes in the grommets? Do you use a particular kind of sealant around these?

I'm not the submarine type but on other cars I've used a product called "PERMATEX BLACK SILICONE SEALANT". It's probably available in many places but I used to get it at Autobahn.
Don't know if it's the best or just another product but it's always done me well in automotive applications

I put about 4x 2core 3mm wire and uhf cable into the large grommet . so do it right the first time and neat and water tight and leave 1 meter each side so when you need to wire up power just use one of the cables, wire up the switch in side the car and power up in the engine bay direct to cable or by a relay. its just save wrecking the loom and seal
and makes quicker installs so the wife can not take it back to the shop once fitted

MP3 said:

Hi Rocky One, if u look under the dash and trace the bonnet catch cable, you will see a rubber grommet the size of a ten cent piece, ive run several wires through this grommet with great success and u can cable tie it to the bonnet catch cable and it looks really neat and proffesional..........hope this helps.

Click to expand...

Just installing a UHF and took a picture for anyone looking running wires through the grommet MP3 was talking about.





Hope that helps.

What a bloody good source of information this forum is, i'm putting my UHF in today, a 3min read of the forum and I have all the info i need to save me scratting around and getting pissed off at the world.
Good on ya fellas