R32 manual box reverse light wiring.

[Rb25orange]

Reverse light are not even hooked up at the gearbox connector, and I don’t see any wiring at all,that indicate they could be for reverse light.  Which could have been deleted from previous owner. 
 Researching through online, Figured out the reverse light wiring is part of this unwrapped harness in the photo. 
Does anyone know which one are they ?

Also once I know the wires how should I proceed connecting them to the box ?

TIA

[GTSBoy]

The wiring diagrams, including wire colour codes, are all available in the R32 GTR manual.

[Rb25orange]

Yea man tried looking into it, couldn’t figure out still. Only transmission wiring I found in that manual is the neutral switch and speedo.

If you know the page no. For whole transmission wiring, that be great. 
Still don’t think it’be same for 20det box

[GTSBoy]

1 hour ago, Rb25orange said:

Still don’t think it’be same for 20det box

The 20DET RWD box and the 26/20DET AWD box both have a reverse switch. The reverse switch wiring will definitely be on the diagram. I'm 2000km away from my copy of the manual, so can't easily look for you. Keep looking.

[Rb25orange]

Will do, thanks.

 

Do you know from memory which of these two plug (red marker) is for reverse switch ? also what is other one for ?

 

[GTSBoy]

One is neutral, the other is reverse. You can actually work out which is which for yourself by probing them. One will be closed (short circuit) in neutral.....the other in reverse.

FWIW, on the small l box, I think the frontmost one is reverse and neutral is the rear one.

[SKYMAGGOT]

Been a while but the switch closer to the bellhousing is reverse

[Rb25orange]

@GTSBoy thanks man, new to using all this. 
can you please have a look at the wiring manual for me. I have tried my best couldn’t find it, would have been easier if I had a pc, it’s terrible on the phone.

[GTSBoy]

I'll have to download a copy of it when I am at the hotel tonight. Wouldn't be a good idea to do it on the borrowed 4G connection I'm using at site.

[GTSBoy]

OK, so, I downloaded the R32 GTR manual that's up on NicoClub's site. On the 3rd page of wiring diagrams (the last pages of the PDF), which I show here zoomed out for identification purposes

Right in the middle is the reverse lamps and the reverse switch (for MT vehicles)) is shown right there, just above it. I've zoomed it in and circled the area of interest, here

The wire that runs along the bottom of the reverse light is earth. If you follow it to the left across the pages of the pdf you will find it ends at the -ve symbol. On the way, it passes both the vehicle speed sensor and and the neutral switch too (as you scan along the diagram). I don't know if this means that there is a buss wire or if it the body earth, but it doesn't matter. This will become relevant later, when I describe probing.

It shows the wire colours, but sadly, this pdf is too low a resolution to be able to decipher them.

I have at least 2x pdfs at home, plus the paper copy that I photocopied myself from a manual I borrrowed from Nissan Australia last century. I'm sure that at least one of the pdfs I have (and my photocopy) have legible wire numbers everywhere.

So what I'm telling you is, find a pdf upload that has better quality (if the one you already have isn't good enough), and have a look at that section. The wire colours are shown each side of the switch.

But, there are still things you can do even without a legible drawing. You can use manual methods to probe the wires. Start with a meter connected to the appropriate side of the reverse lamp wiring in the boot (the side that goes back to the switch, not the earth side that I described above) and probe around the gearbox loom under the car until you find continuity. That should be one of the wires. Then, the other wire is known to go to IGN relay 2, shown on the next page of the pdf, with the interesting parts circled n the below image. That wire code circled is the lower wire of the pair that comes in from the left, which is the same wire that leaves the previous page on the right, having come through the reverse switch. You go find IGN relay 2 and you can identify the wire coming out the relay that delivers 12v to these circuits, and probe looking for continuity to wires in the gearbox loom.

As a further plus, the neutral switch should be 2 of the other wires in the gearbox loom. One of them will be earth and the other one will go back to the appropriate terminal on the ECU, which I think is 44, but you should double check with the ECU pinout.

Edited July 1, 2021 by GTSBoy
spellink

[Nathan rfb]

I have recently brought a R32 that had been manual swapped it had no wiring running down to the tranny that is supposed to Be next to the fuse box in the engine bay, the reverse light switch is not hooked up and the only thing I see the old owner done right was bridge the inhibitor so the car can start, does anyone have photos of wat plug and pinout is used for the to wires on the reverse light switch

Also the 3pin plug in the middle wat is it for?

 

[Rb25orange]

@GTSBoy

thanks mate, been totally strapped at work didn’t get a chance to look up here, at the time rwc guy turned back, was too keen to see em reverse lights so did a bit of dodgy job wiring it straight from the box to rear lamps hahaha, and had him back and should have taken a photo of him smiling lol,

 

 

@Nathan rfb

Mate not too sure how different it might be on a auto loom, 

green (grey dots)

green/white trace 

was the wiring for me from the big connector next to the fuse box in engine bay area. Same has wiring for neutral switch green/o from memory.

If this doesn’t help, the MIGHTY METER worked out for me in the end.

[Rb25orange]

On 04/02/2022 at 3:53 AM, Rb25orange said:

big connector next to the fuse box