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A couple of years ago I swapped my auto box over for a manual. The reverse lights never worked due to the plug for the manual box being missing, but I see the new MOT regs will require reverse lights to work, so I had a look at the wiring diagram in Haynes. I can't remember if the auto has a plug on the box, I don't think it did I think it is done via the auto selector switch. So I reckon the wiring towards the rear lights are in there somewhere but I need to get the plug for the manual box and the wiring and hook it up.

Has anyone ever done this and is there a simple way to get the wires hooked up to the existing/remaining loom that is there. I'd need to get a plug and some of the wiring from something like perhaps a corsa or astra.

Thanks

C

I can't help with the wiring but you don't need to worry about the new mot for your reverse lights - it only applies to cars registered from sept. 2009
https://www.gov.uk/government/news/mot- ... 0-may-2018

matt

ilovedmymantas wrote:I can't help with the wiring but you don't need to worry about the new mot for your reverse lights - it only applies to cars registered from sept. 2009
https://www.gov.uk/government/news/mot- ... 0-may-2018

matt

Woopdeedoo! Scored that off my list of things to do!

Cheers

Andrew

Usually with non-functional wiring plugs, they are still wired to the loom and tucked away somewhere in the engine bay. So you'd need to have a rummage in the engine compartment, most likely somewhere around the battery side, as I believe reverse light switch units were fitted to the front of gearboxes on the manual models, I think it's just a 2-pin plug, so if you still wanted to get it sorted, then find the plug, a new switch and job done.

Even if you don't technically need them for an MOT, they are still important, if you're reversing onto a main road, how can anyone driving on that road tell which direction you're intending to drive in from a distance? It's a safety aspect at the end of the day.

Cavalier342 wrote:Usually with non-functional wiring plugs, they are still wired to the loom and tucked away somewhere in the engine bay. So you'd need to have a rummage in the engine compartment, most likely somewhere around the battery side, as I believe reverse light switch units were fitted to the front of gearboxes on the manual models, I think it's just a 2-pin plug, so if you still wanted to get it sorted, then find the plug, a new switch and job done.

Even if you don't technically need them for an MOT, they are still important, if you're reversing onto a main road, how can anyone driving on that road tell which direction you're intending to drive in from a distance? It's a safety aspect at the end of the day.

I do want to get them sorted tbh, I did have a rummage about the bay, there isn't anything looking like an existing plug as the auto didn't have the reverse plug. I think the wiring is from the autobox switch under the dash and was activated by the selector. So I am having a look at the loom that was left with a view to wiring that up to the reverse switch on the manual box. There is a switch just not the plug for the reverse wiring.

Reverse light feed is fuse 22.
Look for the barrel shaped connector next to the battery.
This is referred to as X5.

The wiring route is as follows.
Black wire from Fuse F22 to X5 pin 12.

This black wire goes to the reverse light switch.

The return from the reverse light switch is the black/white wire on X5 pin 2.

The black/white wire goes from X5 pin 2 to X6 pin 1. (X6 is the main connector in the passenger footwell).

And from X6 pin 1 to the reverse lights in the rear clusters.

So to test the theory - short X5 pin 12 to X5 pin 2 with a piece of wire.

Turn on the ignition and the reverse lights should come on.

If this works, then connect wires from the reverse light switch across the two pins on X5 (and remove the shorting wire of course).

Hope that helps

Robsey wrote:Reverse light feed is fuse 22.
Look for the barrel shaped connector next to the battery.
This is referred to as X5.

The wiring route is as follows.
Black wire from Fuse F22 to X5 pin 12.

This black wire goes to the reverse light switch.

The return from the reverse light switch is the black/white wire on X5 pin 2.

The black/white wire goes from X5 pin 2 to X6 pin 1. (X6 is the main connector in the passenger footwell).

And from X6 pin 1 to the reverse lights in the rear clusters.

So to test the theory - short X5 pin 12 to X5 pin 2 with a piece of wire.

Turn on the ignition and the reverse lights should come on.

If this works, then connect wires from the reverse light switch across the two pins on X5 (and remove the shorting wire of course).

Hope that helps

Cheers Robsey will have a look at that. I was looking at the big X5 plug but I thought since it was an auto it wouldn't be there, that the fuse 22 would go into the autobox wiring, which is now neatly parked under my dash! Will try that anyway.

Cheers

Andrew

Looking at the auto box wiring,

The black wire from Fuse 22 goes direct to the autobox (does not go through X5 pin 12 ).
On the autobox this is connector X47 pins A and D. X47 has approx 7 wires going to it.

The other 4 pin connector is X46, but is not required here.

So you may need to feed an ignition live wire between Fuse 22 direct to the reverse gear switch.

The black / white wire does appear to go to X5 pin 2 and on to X6 pin 1.
On the autobox connector X47 it is pin B

So if needs be, insert a wire direct from the other pin of the reverse gear switch, and run this to pin number 1 of the big connector in the passenger footwell.(connector X6).

I hope that makes sense.

Robsey wrote:Looking at the auto box wiring,

The black wire from Fuse 22 goes direct to the autobox (does not go through X5 pin 12 ).
On the autobox this is connector X47 pins A and D. X47 has approx 7 wires going to it.

The other 4 pin connector is X46, but is not required here.

So you may need to feed an ignition live wire between Fuse 22 direct to the reverse gear switch.

The black / white wire does appear to go to X5 pin 2 and on to X6 pin 1.
On the autobox connector X47 it is pin B

So if needs be, insert a wire direct from the other pin of the reverse gear switch, and run this to pin number 1 of the big connector in the passenger footwell.(connector X6).

I hope that makes sense.

Hi Robsey

It doesn't quite make sense - yet - I will need to sit with the electrical diagram and also the wiring loom and figure out a bit a a time. I'm a seeing/doing type of person when I learn however what you have provided is probably the best logical explanation of the set up and what to do and look for. Very much appreciate the explanation and the references to it all.

Cheers

Andrew

In simple terms Andrew...

1 - make up 2 lengths of wire.
Each approx 3 to 4 metres long
The wiring diagram specifies 0.75mm csa stranded wire for both wires
2 - connect one end of each wire to the reverse light switch.
3 - Thread both wires through the bulk-head with the main loom.
4 - Run one wire across the back of the dash to fuse F22.
5 - Run the other wire down to the big connector in the passenger foot-well.
Connect the wire to pin 1.





And you should have working reverse lights when the gear stick is in the reverse position and the ignition is on.

My thoughts for auto to manual conversion of electrics. There are two main differences if automatic transmission will be changed to manual - starter circuit and reverse switch.
Changes are as simple as that and it can also be undone easy: locate X46 in engine bay. It's the 7-pole connector at the AT-switch. If you remove the wiring harness for AT this connector with stay unconnected, because it runs to engine wiring harness.

For starter circuit: connect E to G with minimum 2.5 mm² wire.
Reverse lights: run two wires from A and B (0.5 mm²) and a 2-pin-connector to reverse switch.

It will only work if engine harness was not changed from AT to MT (then X46 is missing). Maybe it's useful to someone.