Using Rear foglight switch as lightbar switch

**EvilGTV** · 24th June 2014, 04:45 PM

Yep, I just played this game. I'm going to guess that you've run power into pin 1, and then used the ground wire on pin 4 to turn on your relay. Unfortunately, it won't work that way. Pin 4 MUST go to straight to ground if you want the illumination and/or the led to operate, as it's a common ground for both those items. If you have it wired as I suspect, you effectively have 12v coming OUT of pin 4 when the switch is turned on - therefore no difference in voltage, and no workies.

Pin 1 can be used to EARTH your driving light relay, then use the illumination wire in the dash to pin 2, and ground pin 4. So power is supplied to one side of the relay, then from the other side comes back to pin 1 on the switch. When the switch is pressed, pin 1 is connected to pin 4, and the circuit is then connected to ground. Pin 4 is always connected to ground, so the illumination will work any time there is power supplied to pin 2.

And if you want the led to work, you need to run a wire from the output of your driving light relay into pin 5, so any time the relay is switched on, it supplies 12v to pin 5, which is connected via the led to - yep, that's right, pin 4.

Clear as mud? I can do a sketch if it'll help. I actually ran two relays in the end - I wanted my driving lights only to come on with high beams, and by picking up the high beam wire under the dash, and sticking a relay in there too, I got away with only running a single wire to the front of the car where the other relay that actually turns the lights on lives. That wire is the earth side of the relays, so if it shorts all that happens is my driving lights turn on, no melties.

*EDIT* Interesting... I see someone has already put some pinouts up, but they certainly don't agree with how my switch was configured... Those pinouts I've given are taken straight from how it's currently wired in my car, but I think mine may be a rear wiper switch from memory, which may explain the difference? Best to check with a multimeter maybe...

**Nova** · 24th June 2014, 06:04 PM

Treasure trove of info here -
http://www.aulro.com/afvb/discovery-...-circuits.html

Cheers,
Nova

**dwarfmarine** · 24th June 2014, 07:04 PM

Originally Posted by EvilGTV

Yep, I just played this game. I'm going to guess that you've run power into pin 1, and then used the ground wire on pin 4 to turn on your relay. Unfortunately, it won't work that way. Pin 4 MUST go to straight to ground if you want the illumination and/or the led to operate, as it's a common ground for both those items. If you have it wired as I suspect, you effectively have 12v coming OUT of pin 4 when the switch is turned on - therefore no difference in voltage, and no workies. ..

Yeah if you don't Mind doing a sketch (or like I've done below)
The wiring for the harness had 3 wires,
(Was connected to a 3 way switch, but is really
Only an on/off switch- it's a universal harness for the combo flood/spot lightbar so they can be activated individually-
Mines not a combo so it's a straight on/off
One wire runs to the relay
The other to the positive battery terminal

I've only got it setup straight to the battery so it can be turned on without the car being on- simply for convenience

So it's wired as below-
1: relay
2: nothing
3: not used
4: positive battery (fused)
5: not connected
As mentioned- this works fine for turning the lightbar on and off- however pin 2- as per the factory wiring diagram- actually does nothing when connected to either illumination from the cruise switch above or when grounded
Pin 5, which is earth, according to factory, illuminates the led on light when connected to illum.

So from what I understand from what you've said:
1. Positive battery terminal
2. Illumination (tap into pin 2 for the cruise switch above)
3: not used
4: ground to chassis
5: run to relay, also run to pin 4
Is that correct?

Can I just use the instructions in post #7 of Novas link?- cheers Nova- to swap the pins to the right position rather than un-soldering and re-soldering?
(My soldering iron is on the fritz, so I used the Narva heat shrink'eze'solder- heat shrink with low melt solder in it)

**PaulMc0308** · 24th June 2014, 07:18 PM

The Freelander-1 cruise control switch is wired exactly the same as the D2 cruise control switch, and the Defender Puma heated seat switch (also the same as the 2002 TD5 Defender and D2 heated seat switches), as detailed in post above -

Pin 1 - Live in from fused supply
Pin 2 - Dash illumination
Pin 3 - Not used (but is internally connected to Pin 5 - Earth)
Pin 4 - Switched live out to accessory
Pin 5 - Earth

There appears to be some confusion as to how these switches are wired.

They are not all the same.

Although they are all made from the same basic switch body, the design of the brass circuit track inside them, allows for their circuit to be configured to suit their function and the vehicle's wiring.

It is possible to make alterations to some of the switch's internals, to change the way the circuits are switched - but, it's easier to find a switch that left the factory with the configuration you need.

DIFFERENT SWITCH TO ABOVE

This is a different switch to the one we were discussing previously.

I've posted this here to show how these switches are constructed and their circuits created.

This is the Defender spotlights switch YUG000540LNF dismantled, showing the pins numbered from 1 to 5, and where the switch contacts switch across pins 1 to 4 -

This is the internal layout, which switches the earth from a relay across pins 1 and 4 -

By cutting the track at the point marked in Red, the internal circuitry of the switch is changed so that pins 3 and 4 are no longer on the same circuit.

This means that you can switch a live from pin 1 to pin 4, and use pin 3 as the switch's earth for the LEDs

Paul.

1989 Arles Blue 2.5TD 110 Hardtop
1999 Epsom Green Discovery II 4.0 V8i 'XS'

.

**muddy** · 24th June 2014, 07:56 PM

http://www.aulro.com/afvb/90-110-130...ne-switch.html

Paul
as above post 1 shows reverse for pins 4 and 5 and appears to be copied from a manual . I can recall also seeing the connections the same as you are quoting ---your thoughts please as I have connected up as per your 4/5 and get the reverse indication (on no indication and off when indication)
Maurice

**PaulMc0308** · 24th June 2014, 08:51 PM

Originally Posted by muddy

Traxide, spotlights and a genuine switch

Paul
as above post 1 shows reverse for pins 4 and 5 and appears to be copied from a manual . I can recall also seeing the connections the same as you are quoting ---your thoughts please as I have connected up as per your 4/5 and get the reverse indication (on no indication and off when indication)
Maurice

I drew that switch and variations on it, several years ago, using PowerPoint.

I saw your post in that thread, regarding your Mulgo switch.

I can't find switches on Mulgo's website anymore - however, the last time that I looked, I downloaded their instruction sheet (attached), which would suggest that they used Defender Puma heated seat switches as the basis for their switches.

These are wired, as in my post above -

Pin 1 - Live in from fused supply
Pin 2 - Dash illumination
Pin 3 - Not used (but is internally connected to Pin 5 - Earth)
Pin 4 - Switched live out to accessory
Pin 5 - Earth

and confirmed by the attached Mulgo instruction sheet.

Paul.

1989 Arles Blue 2.5TD 110 Hardtop
1999 Epsom Green Discovery II 4.0 V8i 'XS'

.

**EvilGTV** · 24th June 2014, 09:00 PM

Paul:

In the picture you've attached, before you modified the board, pin 4 is the common earth. Note that the two LEDs each have a leg on the track leading to pins 3 and 4, and when the switch contact is slid to the 'on' position, it provides a path between the track from pin 1 to the track to pins 3 and 4.

Pin 5 is the power feed for the red led, pin 2 is the power feed for the switch illumination.

**EvilGTV** · 24th June 2014, 09:10 PM

Disregard this, see Paul's post 2 below here.

**PaulMc0308** · 24th June 2014, 09:17 PM

Originally Posted by EvilGTV

Paul:

In the picture you've attached, before you modified the board, pin 4 is the common earth. Note that the two LEDs each have a leg on the track leading to pins 3 and 4, and when the switch contact is slid to the 'on' position, it provides a path between the track from pin 1 to the track to pins 3 and 4.

Pin 5 is the power feed for the red led, pin 2 is the power feed for the switch illumination.

That's correct.

That picture is of YUG000540LNF - The Defender 'spotlights' switch, which is an earth-switching switch.

The following switches -

Defender Puma heated seat switch

Defender TD5 / Discovery-2 heated seat switches (same part numbers)

Discovery-2 cruise control switch

Freelander-1 cruise control switch

are all live-switching switches, which should be wired, as detailed here - http://www.aulro.com/afvb/discovery-...ml#post2171306

Paul.

1989 Arles Blue 2.5TD 110 Hardtop
1999 Epsom Green Discovery II 4.0 V8i 'XS'

.

**PaulMc0308** · 24th June 2014, 09:24 PM

Originally Posted by EvilGTV

If you do what Paul has suggested and snip the link where he has marked the red line, you can make that work without changing what you have on pins 1 and 4.

You would need to then have:

1: relay
2: illumination power feed
3: earth
4: positive battery
5: power taken from the output of your light relay (if you want the red led on when the light bar is on.

I'll draw the other option in a minute.

Land Rover wire pins 1 and 4 the other way round -

Pin 1 to the battery positive

Pin 4 to the relay

The live-switching switches have the 'tell-tale' LED wired to the output (pin 4), with the switch's earth on pin 5 (and pin 3).

The earth-switching switches, that have a 'tell-tale' LED, have the tell-tale's live on pin 5, with the switch's earth on pin 4 (and pin 3).

Paul.

1989 Arles Blue 2.5TD 110 Hardtop
1999 Epsom Green Discovery II 4.0 V8i 'XS'

.

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