S14 loom relocation, what im doing

**Pics will be uploaded this evening when i get home from work***

Afternoon all,

Just going to start a thread on how I have gone about relocating the wiring loom on my 14a. As we all know the way that Nissan ran it was pretty stupid, as soon as you lower the car a decent amount you damage the loom and everything breaks causing loads of wired and wonderful issues, iv done it many times. if things like the central locking stop, the heater blower no longer works and the power windows stop working, chances are its the arch loom.

I have been wanting to do this for some time, and did allot of research on it, trying to find the best information possible on it, but everything out there is pretty rubbish. I never managed to find a decent guide to reference to and get info from. All that I could find was either pictures of it completed, or a how- to showing something like ‘take the dash out, unplug some things, magic happens, tadah done’, not helpful.

I am doing this for reference, its not going to be a set guide, every car could be slightly different. Its defo not a how to, so don’t try to blame me when you do it and your car doesn’t start or it has a mental electrical fire.

If I can help people out who want to tidy the bay up and save the arch loom then that good with me.


More to follow

Before you get cracking on your own car, take a good while to see where everything goes, what is plugged in where, where cables are routed, what could possibly be in the way etc.

Also I would recommend taking photos, lots of photos. This gives you reference to go back to when you inevitably forget what should be plugged in where, if not were going to get many new ‘where does this plug go’ threads in here.

Next up I stocked up on electrical supplies from the good old E of the Bay. Things like Solder, heat shrink, electrical tape, electrical connectors, cutters, crimping tools and a soldering stand for holding the wire that you plan on re joining. Buy it in advance, chances are your going to need it at some point, so get it now before you get in the wiring groove. It’s a pain having to wait several days for supplies to arrive. Also a decent soldering iron if you don’t already have one, I have a gas powered one that I like, and an electric one from Lidl as a backup.

Also I would get a decent label maker, I acquire one from work but its going to come in handy later on.

The last thing that’s on your supplies list is wire, now there are two options here. If you like making your life hard and don’t want to make future fault finding easier then just buy some different gauge wire and get cracking. However if you want to do it properly your going to need to get the wire that’s the same colours as the OEM Nissan loom. You could try to get another full s14 engine bay loom and cut that to bits but that has two problems. 1st is that there getting more and more expensive, I was looking at around £80+ for the loom, and I don’t have a magic money tree like Mr Corbyn so that was a no go for me, 2nd is that your going to be cutting up a perfectly good s-body loom that someone else could need, and I couldn’t bring myself to waste a whole loom just for the wire.

So thanks to Pointz on here for the brilliant idea, head to a scrapyard and get your hands dirty. Find one of these –

https://uploads.tapatalk-cdn.com/201...bf9502867c.jpg

Take the dash out, its easier in a scrappy as you haven’t got to be careful with the dash or the rest of the car, so a hammer is a great way to get the dash out quickly (I recommend taking the funny security torx bits to get the steering wheel off as well, I didn’t and it’s a pain to do this with the steering wheel on like I had to do).

Then remove the whole interior loom and as much of the wiring as possible, most of it unplugs but there are some that were harder to get at so we just cut them off at the plugs.

That leaves you with this

https://uploads.tapatalk-cdn.com/201...dec31affb6.jpg

And leaves the Micra like this

https://uploads.tapatalk-cdn.com/201...0d12a2963d.jpg

* I would guess that you don’t have to stick to the Micra, a Primera or any other Nissan of that generation should be OK, but I know that its not that hard to get the dash out of the Micra*

**When taking all of the trim out its worth pocketing all of the screws that were holding stuff in, its inevitable that you will lose some out of the SX when you take that apart so having a spare stock of OEM Nissan hardware cant be a bad thing**

You now have an OEM Nissan loom to cut about without a care in the world, means that you haven’t got to live with yourself for cutting up an s-body loom!

Also just a point, don’t do this on a 32 degree day, its bloody hot sat in a Micra cutting bits out, think me and LP1121 nearly died in there it was that hot.

Now you can finally head to your rusty old Datsun and start pulling that to bits, just more carefully that the Micra, this ones got to go back together!

First job I did was take the bonnet off and empty the bay of as much as possible that’s going to be in your way, I took the bumper, headlights, wings, doors ETC all off as well as removing all of the I/C and pipework and the radiator. Make sure that when you do this you cover the turbo inlet/outlet and the plenum inlet, you don’t want any crap getting in there and causing engine issues when you next start the car. I cable tie sandwich bags over all of the inlets and outlets to protect them from debris.

https://uploads.tapatalk-cdn.com/201...0f1b3171e2.jpg

https://uploads.tapatalk-cdn.com/201...23f35e1b83.jpg

So now you have as much out of the bay as you need, if you have more stuff in the bay like horns, alarm sirens ETC it might be worth removing it all. Here I recommend that you take that label maker that you brought/acquired and label everything electrical that you have unplugged so far, these ones are pretty self explanatory as its things like headlights, indicators ETC but why take the risk down the line.


Next up you can start on the interior, the dash and all associated parts will need to come out, but its not to hard. Firstly get rid of all of the centre console and arm rest, unplug all of your radio ect, heater controls and any of your choice gauges if you have them. Then take the speedo clocks out, the glovebox comes out and remove all of the trim around and under the steering wheel and the trim for the vents at the front of that dash where it meets the windscreen (that’s fragile so be careful not to snap it when taking that out). And atchilly, if you don’t have a snap off take the steering wheel off as well.

Next up is taking the dash itself out, there should be many bolts around the place for holding it in place, unless its like mine where there was about 4, I will try to make an image with all of the locations of where the screws are located to take it out, if I can I will put it below.

Now you have access to the loom, its looks daunting and a complete mess, but take you time and think about what your doing. Be careful when unclipping things because if you break a plug its just going to mean having to repair or replace it down the line, so taking your time here can save you time and hassle in the long run.

https://uploads.tapatalk-cdn.com/201...3464c0eab0.jpg

First thing I did here was label everything that I unplugged from the dash, radio, heater, speedo and anything else in there. Then unplug and label everything that plugs into the indicator/light stalks and the ignition barrel. Then we started to look at how to extract the arch loom from the car. The loom itself is plugged in above the interior fuse box, your looking for x2 massive plugs, one is grey (interior loom) and one is white (arch loom) it’s a massive white plug that’s screwed in for security so it cant come loose. The loom then extends up the column and has all of the indicators ETC on it, so all that will need to be pulled through as well.

https://uploads.tapatalk-cdn.com/201...1870e47540.jpg

https://uploads.tapatalk-cdn.com/201...22282cfbcd.jpg

Below the two plugs is the fusebox and relays, unbolt this as well as its easier to get to everything being able to move it arround.

https://uploads.tapatalk-cdn.com/201...d70ef4f3c8.jpg


When you have all of the arch loom that’s in the car unplugged you can start looking at pulling it through the hole in the arch, probably easier to have a second pair of hands here. Make sure that everything is un cable-tied over the arch and either put the car on full right lock, or take the wheel off. The grommet in the arch should just be able to be wiggled out around the loom, then you start to feed all of the loom that’s in the car outside.

https://uploads.tapatalk-cdn.com/201...3f60506de5.jpg

*Note here that the big while plug has a protective cover type thing around it, you need to take that off the plug. If you don’t it wont fit through the hole in the arch*

After the large plug is through its easy to pull the rest through. And there you have it, the looms unplugged and out of the car, you’ve started the loom move. Go grab yourself a beer!

https://uploads.tapatalk-cdn.com/201...0ecbea6d3e.jpg

Next up you need to get the bay fuse box unplugged and removed form the bay completely. There are different connectors around the bay so take pictures and label things.

First thing I did was get the wiring out that is clipped under the front slam panel, its in lots of plastic protective sheathing so feels quite chunky but unclips. Once that’s out you can trace the loom round the bay to the hot side, there is a large plug with x2 wires into it that connect the two sides of the loom together, mine were orange and yellow but I don’t know if that might change on different years? I hope not that would be stupid. Get that unplugged and you can now look at disconnecting the starter and gearbox looms, these come out of the bay fuse box.

https://uploads.tapatalk-cdn.com/201...279383911f.jpg

The starter and gearbox loom are pretty self explanatory to unplug, they come out of the rear of the bay fuse box and go down under the inlet, find the plugs as pictured below and unplug them. Remember, take pictures and label things.

https://uploads.tapatalk-cdn.com/201...edd2cdefd3.jpg


There may also be a power cable that needs to be unplugged here, may be bolted into the back of the fuse box, again may be different on mine to others because of the battery relocation that’s been done and needs doing again as its dodgy as fook.


Now you should be able to remove the whole bay loom from the car, if you unplugged everything correctly that is.

https://uploads.tapatalk-cdn.com/201...e8dcea876f.jpg

*Note here that my headlight wiring had been very bodged in the past by previous owners, I haven’t yet figured out if mine is correct, but I highly doubt it is. So you may take some of the headlight wiring out at this step as well*

So now that you have the bay loom out you can take the opportunity to make sure its in good condition. I knew that my arch loom wasn’t in the best on condition and had been repaired in the past by me and previous owners, so now is the time to make sure that all the repairs are good and there is no exposed wires or broken wires.

I opened the whole arch loom up to inspect, I new there was some to do but not this much, someone has been busy in the past bodging this. I am having to repair about 1/3 of the arch loom, I doubt yours will be this bad. Just do one wire at a time to make sure that you don’t get muddled up. You don’t want to connect up the wrong wires, that will be a right pain to fix in the future if you do.

https://uploads.tapatalk-cdn.com/201...fb22b9a45d.jpg

So I set about repairing the loom damage, cutting out all of the old and soldering in new wire from the Micra loom. It took a while but its well worth doing for your own piece of mind.

https://uploads.tapatalk-cdn.com/201...9fa074a995.jpg

https://uploads.tapatalk-cdn.com/201...b1fe556123.jpg


I have also taken the time to get some proper loom tape, rather than just using electrical tape I’m using TESA loom tape (ebay item no - 252417584983). Plan is to strip all of the sheathing off the look and replace it all with this. Gives it a freshen up and look much better that the factory stuff they used.

Now that the loom is repaired you can set about getting the interior prepped for the loom to be installed. I decided that the first job was to remove the dash bar from the car. This needs to be modified a little so removing it and giving it a lick of paint wont do it any harm.

https://uploads.tapatalk-cdn.com/201...8426980e41.jpg

https://uploads.tapatalk-cdn.com/201...29e9dd4fb2.jpg

Once its out you need to cut off the tabs for the airbag, there not needed in my case so I removed them, sanded any sharp edges off and painted it. This is where the fuse box is going to be placed after the relocation so they need to be out of the way for future mounting of the fuse box. If your intending on keeping the airbag you may need to have another think about what your going to do here, you may be able to mount the fuse box lower down and remove the glove box? I haven’t looked into this so what to do here I’m not to sure what will work best with your situation.

While this is out I also removed the heater blower to allow access to the firewall, anything that can be gotten out of the way cant be a bad thing, its going to make running the cables allot easier with it all out the way.

https://uploads.tapatalk-cdn.com/201...7bf0f92fbe.jpg

For future post6

For future post7

For future post8

For future post9

For future post10

For future post11

For future post12

For future post13

For future post14

For future post15