Spotlight wiring

[TheTree]

Hi

As i am doing my blend motors soon I am thinking about wiring for spotlights.

Get a suspension lock switch (which I believe is the only non-momentary switch in the dash) and install it in the blank spot to the far right, hook into the high beam circuit and connect the switch to that and then to the spotlight relay.

My question is, is there an obvious spot to pick up the high beam circuit?

I am hoping to do it behind the light switch

Thanks
Steve

[Robsrod 58]

Steve,

I used a gizmo that requires you to double pump the high beam to turn on and pump the high beam to turn off, no extra switch required, no need to come back to the dash at all.

Rob

[Keithy P38]

I rekon your best bet would be from the relay. Not sure how they do it in the workshops, but I could find out (got a mate who does that for a living).

[wayneg]

As Keith says, wire them through a relay so they come on with the main beam . Then run the earth from the relay through your switch. 86 on the relay is the + from the main beam Pick that up from the plug on the actual headlamp. 85 is the earth through your switch. You are then only running a thin earth wire through the firewall and switch to turn on the lamps
http://www.farcorners.co.uk/wp-content/uploads/2012/05/15-05-12-Aux-Light-Wiring-Model-DIA-1-600x589.jpg

[TheTree]

Hi

Thanks for the info, I will investigate the double pump widget.

Picking up the 12v from the relay or the headlight makes it much easier to find than under the dash.

I was always going to use a relay to power the spots, and running just the earth back from the spotlight relay to the switch makes a lot of sense :D

Regards
Steve

[p38arover]

Buy the correct P38A locking spotlight switch STC7811

See http://www.aulro.com/afvb/1723213-post12.html

[Pete38]

Buy the correct P38A locking spotlight switch STC7811

See http://www.aulro.com/afvb/1723213-post12.html

I thought that was a momentary switch though?

[p38arover]

No, it's a locking switch. Both Scouse and I have them operating our spotlights.

[TheTree]

Buy the correct P38A locking spotlight switch STC7811

See http://www.aulro.com/afvb/1723213-post12.html

Hi Ron,

I read somewhere that the suspension lock switch was the only non-momentary dash switch, this is obviously wrong !

My initial thought was to re-purpose the rear foglight switch, but I was not sure if it had interlocks with the front foglight switch.

I shall dig a little more :p

Thanks
Steve

[rc42]

The main beam indicator light behind the dash certainly has voltage when the beam is on, as does the headlamp switch itself if you could get to those (or the wires feeding them) and send that through a switch to your spot lamps relay it should do the job.

You could also run two cables from the new dash switch to the headlamp area near the battery and pick up the +12v directly from the wire feeding the main beam bulb on one wire, the other wire could then trigger the relay via the switch.

Another option is to manage without the dash switch and permanently wire the additional lights to operate with the main beam.

[wayneg]

If your vehicle needs to get an annual roadworthy check and you want to get it right, you might want to check on your States regs.


A separate switch for on/off accessory lights when high beam is activated is required d

My wiring diagram and comments conform to that regulation possibility

[p38arover]

I read somewhere that the suspension lock switch was the only non-momentary dash switch, this is obviously wrong !

I can see I'll have to take a photo of the switch in on and off positions.

[TheTree]

I can see I'll have to take a photo of the switch in on and off positions.

Ron

I believe you because before I even started this thread I was pushing some of the buttons on the dash and noted a few of them locked on and thought "what i read does not seem correct"

So as far as I am concerned you are correct, in fact there seem to be several which lock down ;)

Regards
Steve

[p38arover]

The locking switch is for the driving light kit which, I believe, is not connected via the BECM (I'd have to check RAVE). Devices controlled by the BECM probably only need momentary action switches as the BECM controls the device.

[TheTree]

Hi

I think I will stick to a solution which is known to work , and use the light switch!

Thanks
Steve

[KevinM]

I have purchased the front fog light switch together with the plug and wire still connected for my P38A to wire up the driving lights as stated in this previous forum. I was looking for the wiring diagram to hook up the switch to the relay to make it work as mentioned. Does the tell tail light work when it is wired up.
Any help would be appreciated - thanks.

[TheTree]

HI Kevin

Essentially you need to put a suitable relay (20A minimum) and since it is a P38 i would use a diode protected relay, in a good spot under the bonnet then connect one terminal (86) to your power source and connect the lights to (87).

Terminal (30) which trips the relay needs to go to your high beam wire and the earth terminal (85) needs to be run back through the firewall to one side of your switch, and the other side of the switch goes to an earth point.

When you turn the switch on, it will complete the circuit and as long as high beam is on, the spots will fire up.

Not sure if the light will illuminate, but fairly certain it will when high beam is on.

Regards
Steve

[benji]

Yeh that's correct Steve, I was looking at exactly that on RAVE this morning.
All the front lights on the p38 are positive switched with a common earth, so you can't use the negative as a highbeam pickup.

[Hoges]

IIRC there are a couple of spare relay spots on the fuse box which might be useful... though it may mean a little "surgery" to ensure they're not otherwise connected.... just a thought;)

[KevinM]

Hi Steve, Benji & Hoges
Thanks for the replies. Can you tell me what the difference is between a normal delay and one that is diode protected. The lights I purchased(from China) came with a 40 amp relay that are to power up the two HID's spotlights. When you say connect up to the main beam is that the blue/green behind the second high beam light (mine is a 2001 P38A). On the fog light switch(front) that I purchased to use as the switch for the spotlights, there are six wires - 3 x black that are looped into one which I understand to be the earths, 1 x red/white, 1 x yellow/red, 1 x red/yellow. Are you saying that the earth terminal (85) should be connected to one of these coloured wires (which one?) and then the black run to a suitable earth. On the circuit diagram for the foglight switch, it looks like that the switch mech is connected to the red/yellow wire.
Hoges you said "IIRC there are a couple of spare relay spots on the fuse box which might be useful" where do I find them and how do you know if they are used elsewhere and how would you connect them up? or is it easier just to use the relay I have or buy a diode protected one.
Hope you can enlighten me further.
Regards Kev

[mtb_gary]

Kev

When the light switch is switched on, the supply voltage is applied across an inductance and the current through it increases linearly. As it does so, a magnetic field is created around the coil.

When the light switch is switched off, the coil is disconnected from the supply. The current through it is abruptly interrupted and is no longer able to maintain the field. The field which has been established therefore collapses very rapidly. In doing so it causes a voltage to be impressed across the coil and because of the speed at which the field collapses this voltage can be very high.

Since the direction of the field is changing in the opposite direction to that which caused it, the voltage induced across the coil is opposite in polarity too. Hence "back-e.m.f.", but it's certainly not negative-going.

Unless something were done about it, the collector voltage could rise so far above the supply value that damage might be caused.

The incorporation of the diode clamps the voltage at the collector to Vs + Vd, or about 0.7V above the supply.

Basically, if you don"t have a diode relay you may well fry some of the sensitive p38 circuitry with a voltage spike.

Gary

[TheTree]

Gary

Much more detailed reply than I was going to give, well done :p

Bottom line is it's much safer to use diode protected.

Resistor protected relays are available as well, but they suppress the spike rather more slowly than a diode does.

So a 40AMP diode protected relay is what you want

Steve

[wayneg]

I sort of grasp the need for diode protected relays in the main fusebox with circuits controlled by the BECM but I dont see why running a simple set of spotlights on a separate live feed, directly from the battery, switched via a possitive feed (main beam) coming from another existing diode protected relay will be an issue.
Can someone explain. Where is any potential spike going?
Also some relays have a LED, light emitting diode to show they are on. Are these the same as diode protected relays.

[TheTree]

Hi Wayne,

I guess it's like the old joke about why the Irish wear two condoms "to be sure, to be sure" :p

You are probably correct that a diode protected relay is not really required here, but given the cost and hassle associated with damage to any of the electronics on the P38, it's cheap insurance IMHO.

I would suspect the LED only acts as an indicator not as protection, though LED does stand for Light Emitting Diode

Steve

[benji]

I imagine they would be different as an led needs a resister to limit the current. .... and if I remember right the annode and cathodle are reversed in an led?

The lights on the p38s are driven straight from the becm, most likely from an internal relay, but they are field sensed, which is why the becm knows if the bulb is blown.

You can just buy the doide and solder it in line.

[mtb_gary]

The voltage spike comes from the low amperage side of the circuit ie the switching control. It is the energy remaining in the coil that creates the electro magnetic switch that is the problem.

Gary

[TheTree]

Hi,

Gary is correct, if you look at the diagrams around, the diode is across the coil.

If you really want information overload, you can read this :angel:

http://www.autoshop101.com/forms/hweb2.pdf

Regards
Steve

[KevinM]

I did not realize how complex it was going to be just to hook up a couple of driving lights. Is the spare relay (No.10) in the engine fuse box able to be used for the driving lights or does it make it more complex? Is this relay a diode protected relay? or does it need to be?
Back to the switch, which wire/s do you need to power up to make the switch turn on.
In the wiring diagram that Steve has shown previously in this thread by switching the power on by earthing the relay through the switch, will this protect the BECM from spikes when the switch is turned off if a diode relay is used?
I have certainly learnt that you just about need to be a professor to understand the electrical system of the P38 or you need information overload to try and comprehend.
Regards
Kev

[Pete38]

To be honest, the diode is a pretty standard thing to do in just about any relay circuit and it's not p38 specific.

Yes the diode will protect the spike in his diagram. I've got some idea about electrical/electronics but I'm sure someone else will confirm.

[TheTree]

Hi Kev

I think we are losing the forest for the trees :p

Personally I would just go down to my local Burson or Auto Electrical store and buy a 4 pin diode protected relay.

Given the complexity of the P38 i would stay away from using anything in the fusebox.

The earth lead will not cause any spikes.

Here is a much simpler page on relays and is all you need to know really.

12 Volt Car Relays Used In Automotive Industry (http://www.accessconnect.com/car_relays.htm)

If you do get a relay, let us know and we will double check the pins for you

Regards
Steve

[Pete38]

Anyone got the pin diagram for a standard height exhibit switch?

Also the bulbs are incandescent bulbs are they? So don't need a certain polarity? As I'm switching ground through my switch I'll need to supply power to what's usually a ground.

It should be possible to get the bulbs working yes? Particularly the bulb for when the switch is closed.

Edit: If all else fails I'll pull the switch out and get a volt meter onto it I guess.

[KevinM]

Hi Steve

I will go down to Burson today and purchase a four pin diode protected relay. When I have it, I will come back for some further assistance so that we can get out of this forest.
Regards
Kev

[TheTree]

Anyone got the pin diagram for a standard height exhibit switch?

Also the bulbs are incandescent bulbs are they? So don't need a certain polarity? As I'm switching ground through my switch I'll need to supply power to what's usually a ground.

It should be possible to get the bulbs working yes? Particularly the bulb for when the switch is closed.

Edit: If all else fails I'll pull the switch out and get a volt meter onto it I guess.

Hi

I would imagine that the power for the bulbs could be picked up from one of the other nearby switches, since from the description it has the extra connections on the back.

Yes a multimeter and a 12V power supply should sort the mystery out !

Steve

[mtb_gary]

Hi,

Gary is correct, if you look at the diagrams around, the diode is across the coil.

If you really want information overload, you can read this :angel:

http://www.autoshop101.com/forms/hweb2.pdf

Regards
Steve

Steve

Not a bad read, straight forward complete with pictures ;)

Gary

[KevinM]

Hi Steve & Others

Finally, purchased a Relay with diode protection. Jaycar could not help. Ended up at Repco and have purchased a Narva P/No. 68032 which is 12v, 40amp, 5 pin with diode. Could not find a 4 pin one anywhere. Basically the same but with dual outlet 87 & 87A. Here is the link to the circuit diagram [URL="http://www.onlineautomotive.com.au/Narva-Normal-Open-Contacts-5-Pin3?keyword=68032&description=1&model=1"]
It is not completely correct as it does not show the diode between 85 & 86 but that is where it is and the current runs in that direction from 85>86.
Attached are the wiring diagrams for the fog light switch and the main beam headlights.
My thoughts were to take the power off the high beam wire (blue/purple UP) just behind the right hand main beam 2 and connect to the relay.
If you can assist with what needs to be connected where, I would greatly appreciate your assistance - thanks.
Regards
kev

[wayneg]

87a Not used ( cover/ protect this terminal as it will become live when lights are off Or use a 4 pin relay )

87 +poss feed out to lights

30 power from fused feed from battery

86 Power from main beam + poss feed

85 Through switch to - ground

[TheTree]

Hi Kev

It looks like you are picking up the correct high beam feed.

Connect this feed to terminal 85
86 is the earth which runs back to your interior switch.

Your main power should be connected to 30, via a suitable fuse
Your spots should be connected to 87.

That should have you lighting up your way ;-)

Regards
Steve

Correction, Wayne is correct here, 86 is the high beam feed and 85 is the earth feed back to your switch, sorry about that !

[KevinM]

Hi Steve & Wayne

Thanks for the replies.
I notice that you have different views on where to the main feed is connected to 85 or 86. 85 appears to makes more sense where the current will flow from 85 through the diode to 86. The diode should stop any spike going back.
On the fog light switch (through the switch to ground) which wire do you connect to? There are four wires and on the wiring diagram and it shows that the black goes to earth, red/white for interior lamp, yellow/red appears to be the feed and red/yellow to the fog light. I have tried trying to make the switch work as a switch to earth but nothing appears to work. What am i doing wrong?
Can you enlighten me.
Regards
Kev

[Pete38]

I can't remember exactly, but off memory when looking at the rear of the plug, the top left and middle left pins were switched. I measured it with a volt meter.

[mtb_gary]

Kev

I hope you don't mind me interrupting the conversation, but I think your switch might be the problem. The fog light switch is what is referred to as a momentary switch. In basic terms it sends an on signal to the BECM when you push it once then another signal to the BECM to turn off when you push it for a second time. Essentially, using a fog light switch is not possible for the operation you are trying to achieve. The switch type you need is one such as the inhibitor switch (the one immediately to the left of your fog light switches) you switch it on and it stays on.

Whilst I have not done it, you should be able to remove your fog light switch from it's housing and replace it with the inhibitor switch if you want to use a more appropriate looking symbol for the switch.

Gary

[Pete38]

Kev

I hope you don't mind me interrupting the conversation, but I think your switch might be the problem. The fog light switch is what is referred to as a momentary switch. In basic terms it sends an on signal to the BECM when you push it once then another signal to the BECM to turn off when you push it for a second time. Essentially, using a fog light switch is not possible for the operation you are trying to achieve. The switch type you need is one such as the inhibitor switch (the one immediately to the left of your fog light switches) you switch it on and it stays on.

Whilst I have not done it, you should be able to remove your fog light switch from it's housing and replace it with the inhibitor switch if you want to use a more appropriate looking symbol for the switch.

Gary

Oh yeh Gary is right. Hadn't picked up you said it was an Actual foglight switch. I am using the height inhibit switch in mine. You could probably modify the switch by adding a circuit so the momentary switch latched the circuit until power is turned off but that's getting a little more complex.

[TheTree]

Kev

I hope you don't mind me interrupting the conversation, but I think your switch might be the problem. The fog light switch is what is referred to as a momentary switch. In basic terms it sends an on signal to the BECM when you push it once then another signal to the BECM to turn off when you push it for a second time. Essentially, using a fog light switch is not possible for the operation you are trying to achieve. The switch type you need is one such as the inhibitor switch (the one immediately to the left of your fog light switches) you switch it on and it stays on.

Whilst I have not done it, you should be able to remove your fog light switch from it's housing and replace it with the inhibitor switch if you want to use a more appropriate looking symbol for the switch.

Gary

Hi

Going round again here
;)
If you read posts 6, 7 and 8 in this thread, you will see it was decided that this was not a momentary switch !

I wish I has one of the bastards in my hands, a quick check with a multimeter would soon tell :twisted:

Steve

[drivesafe]

Hi folks and this has been an interesting read and here is just a suggestions relating to the type of relay to use.

If you use a diode protected relay, you MUST wire it correctly or you will not only stuff the diode but the relay will be useless as well.

For positive switched headlights, relay pin 85 goes to earth, and the high beam connects to relay pin 87 ( via a switch if required ).

BUT, there is no reason for using a diode protected relay in the first place.

These diode ( spike ) protected relays are designed to reduce EMF, by removing the spike.

There is nothing to be gained in the way of electronics protection if you use one of these relays just as you are not going to risk harming anything if you use a no spike suppressed relay, and most of the relays in vehicles today are not spike protected.

If you already have a relay, spike protected or not, just use it. All your electronics is already protected by built-in protection that is incorporated into every electronic device ever make.

[KevinM]

Hi All

Thanks for all the replies and it looks like that I need to get rid of the fog light switch and use an inhibitor switch. If I use the inhibitor switch, do I need a diode relay or just a normal relay.
The connections to the relay have me a little confused. I believe that the #4 post of this thread by WayneG with the wiring diagram shows 86 is the main beam feed and 85 goes to earth. If this is correct, I believe that I can not use the diode relay that I have because it shows the current flows from 85 to 86. I will need a normal relay.
Your opinions are appreciated.
Regards
Kev

[mtb_gary]

Hi

Going round again here
;)
If you read posts 6, 7 and 8 in this thread, you will see it was decided that this was not a momentary switch !

I wish I has one of the bastards in my hands, a quick check with a multimeter would soon tell :twisted:

Steve

Steve

Some clarification (hopefully) courtesy of the RAVE manual

"CIRCUIT OPERATION

Front Fog lamps

With the ignition switch and side lamp or headlamp

switch on, a momentary operation of the front fog

lamp switch will activate the front fog lamps. A further

momentary operation of the fog lamp switch, or

switching off of the headlamps/side lamps or ignition,

will cause the front fog lamps to be extinguished.

N.B. The front fog lamps will always be inactive

when the ignition is turned on."


Gary

[mtb_gary]

Hi All

Thanks for all the replies and it looks like that I need to get rid of the fog light switch and use an inhibitor switch. If I use the inhibitor switch, do I need a diode relay or just a normal relay.
The connections to the relay have me a little confused. I believe that the #4 post of this thread by WayneG with the wiring diagram shows 86 is the main beam feed and 85 goes to earth. If this is correct, I believe that I can not use the diode relay that I have because it shows the current flows from 85 to 86. I will need a normal relay.
Your opinions are appreciated.
Regards
Kev

Kev

I found this diagram on line (I'm not going to claim it ;)) which will hopefully clarify the connections as well as guage of wire to use. As an electronics vendor "Drivesafe" may be able to verify this diagram.

Gary
https://www.aulro.com/afvb/images/imported/2013/10/966.jpg

[TheTree]

Kev

I found this diagram on line (I'm not going to claim it ;)) which will hopefully clarify the connections as well as guage of wire to use. As an electronics vendor "Drivesafe" may be able to verify this diagram.

Gary


Hi

That looks right to me and is the way I originally interpreted the connections and wrote them up.

The thing is the relay will work either way but will only be protected one way

Steve

[TheTree]

HI

The switch we arrived at was STC8889 - Auxiliary lighting switch, which may not be the same as the fog light switch which is listed as AMR3711.

So it seems there are two different switches:angry:

Looks like the ride inhibit switch with the fascia changed might be the easiest way to go.

Steve

[TheTree]

Hi

To clear up the orientation quesition standards state that 86 is (+) and 85 is earth (-) so it seems my original post was correct after all:p

It's on the first page of this doc

http://www.hella.com/ePaper/Elektrik/Relais/englisch/document.pdf

Steve

[drivesafe]

Hi Gary and that diagram is for negative switched headlights.

Correct me but I think the LR headlights are all positive switched and if so this diagram will do the job.

Hi Steve and there is no such thing as a relay wiring “standard”, the info you linked to is for HELLA relays and covers “DIODE” spike suppressing relays which are polarity sensitive.

You can also get “Capacitor/Resistor” which are not polarity sensitive.

And as covered above, the standard relays do not have any spike protection and are not polarity sensitive.

So if you are using a diode spike protected relay, use HELLA’s instructions, but for ordinary relays, you can wire the coil connects, pins 85 and 86, to work in either direction.

For POSITIVE SWITCHED HEADLIGHTS.

PLEASE NOT, the YELLOW wire connected to the switch in both diagrams, is an optional connection and is there to allow the driving lights to be operated without the need to turn the head lights on and to high beam.

https://www.aulro.com/afvb/images/imported/2016/06/622.jpg

[TheTree]

Hi,

Earlier in the thread it was pretty much agreed it was cheap insurance to use a diode protected relay on a P38, since all the other relays are diode protected.

Someone pointed out the headlights are at least connected to the CANBUS system, since you get bulb failure messages on the dash.

I agree there is no standard wiring, but a diode protected relay should be wired with the correct polarity.

BTW I have been reading about your SC-80 Isolator with great interest, but that is for another thread :cool:

Regards
Steve

[mtb_gary]

Hi,

Earlier in the thread it was pretty much agreed it was cheap insurance to use a diode protected relay on a P38, since all the other relays are diode protected.

Someone pointed out the headlights are at least connected to the CANBUS system, since you get bulb failure messages on the dash.

I agree there is no standard wiring, but a diode protected relay should be wired with the correct polarity.

BTW I have been reading about your SC-80 Isolator with great interest, but that is for another thread :cool:

Regards
Steve
Steve

I am still very much in favour of diode protection.

Gary

[KevinM]

Hi

Attached is the Narva diode protected relay, showing the circuit diagram on its base. Looking at the wiring diagram below (positive switched headlights-pink background in thread #50) can I use this diode protected relay? The relay diagram sort of indicates that the current flow is from 85>86 (unless I am reading it wrong).
This new wiring diagram(pink below in thread #50) shows the switch between the main beam and the relay - all the indications before were that it should be on the earth side of the relay.
I have an inhibitor switch and it appears to work as per a normal switch (creates a circuit according to the meter) not like the fog lamp switch.
Hoping to get it sorted.
Regards
Kev

[drivesafe]

Hi Kev and there is a misunderstanding on how the diode works as a spike suppressor and as such, how the diode has to be connected.

I can not blow up the picture enough to be able to read the pin connections.

Now as Steve has posted, when using a diode protected relay, PIN 85 MUST GO TO EARTH.

And power ( +12v ) MUST GO TO PIN 86.

This may look to be the wrong way round for the diode but the diode is NOT intended to be used to pass voltage/current through it when powering the relay.

The diode is actually connected up in revers AND ONLY FUNCTIONS FOR A SPLIT SECOND AFTER THE RELAY IS TURNED OFF.

WHAT HAPPENS, put very crudely!

When the coil of a relay ( or any electrical coil ) has powered applied to it, it very quickly builds ups up energy and becomes a magnet. No electrical spike problems at this stage!

But when either one of the coil’s connections is disconnected, there is a large amount of energy still in the coil and this energy basically converts from current energy to voltage energy, and a voltage spike is created.

This spike can be thousands of volts but has no current to it.

The diode, wired in reverse, literally shorts the spike either to earth if the positive connection is disconnected, or to positive if the earth connection is disconnected.

Now if you are worried about the potential of a spike harming your electronics and you have an non spike protected relay, you can wire a diode in reverse to the polarity of power to be connected to the relay.

This would mean, you get a diode and connect the end of the diode with the band around it’s edge, to the positive connection of the relay and the unbanded end to the negative or earth connection to the relay.

So Kev, if you want to add a diode to a non diode protected horn or headlight relay, connections as follow.

PIN 86 goes to positive, usually via a switch and then to the high beam wire. You also connect the banded end of the diode to this pin.

PIN 85 goes to earth and the unbanded end of the diode goes to this pin.

But once again, there is absolutely no reason to need to use spike protected relays in any vehicle, old or new. The spike protection is not there to protect your vehicle’s electronic, the spike protecting is there to make sure the relay meats the EU’s EMF requirements.

Again, all vehicle electronics is and has always had spike protection built into every electronic device and for at least the last 25 years, every input pin, not just the power supply pins, but every input pin on IC’s has also been individually protected against voltage spikes.

[KevinM]

Hi
Thanks for the very detailed reply. Firstly, I have reloaded the diagram of the Narva diode relay in a different format so that hopefully you may be able to read it. Let me know if this relay is alright to use.
Your explanation of the diode is starting to make sense.
Does it make any difference if the switch is place in line between the main beam supply to terminal 86 of the relay or between terminal 85 of the relay and the earth, as Steve advocated.

[drivesafe]

Hi again Kev and that picture is much easier for my failing eye sight.

That relay is fine and should be wired up as covered in my last post ( and Steve's post ) and the CE is certification that the relay meets the EMF requirements.

Also, yes, you can fit the switch in either wire and all will work as required.

[KevinM]

Thanks for all your assistance, I will give it a go now with confidence.
Will let you know how it goes.
Regards
Kev

[TheTree]

Kev

Good luck mate, I think you now have enough info to sink a battleship :p

Steve

[KevinM]

Hi

It is the battleship here again. I have finally started to wire it up but have noticed that the wires on the back of the Inhibit switch are only 0.8mm thick. I am placing the switch between terminal 85 and the earth. On the pink wiring diagram above, it shows these wires as 2mm. Seeing that it is only a trigger does it have to be 2mm or is it ok to run 0.8mm?
I do not think the inhibit switch is designed to take higm amps anyhow.
Regards
Kev

[mtb_gary]

Kev

You'll be OK with the 0.8. It is only activating a relay and running 1 small indicator lamp and a backlight.

Gary

[KevinM]

Hi Gary

Thanks for the reply. I will get into it tomorrow amd then we should lights.

Regards
Kev

[drivesafe]

Hi Kevin and as Gary posted, the your thinner wire is fine.

I used the thicker wire in the diagrams as this is a fairly common size wire, but you can easily go to .5mm2 and all will be fine.

Your relay only draws about 150ma and I don’t think your light would draw all that much more and even if it does, the relay will work from as low as 9v so again, you should be fine.

[Scouse]

HI

The switch we arrived at was STC8889 - Auxiliary lighting switch, which may not be the same as the fog light switch which is listed as AMR3711.

So it seems there are two different switches:angry:

Looks like the ride inhibit switch with the fascia changed might be the easiest way to go.

SteveSurely the easiest option would be to spend $20-25 & get the right switch to start with - STC8889.
Google the part number & you'll find several suppliers for the switch. You could even try a local LR dealer (which is where I bought mine from a few years ago).

[Very_Disco]

Since you are only allowed to run spotlights with high beam anyway why not just take you feed to activate your relay from the light itself and don't bother with a switch on the dash. Much easier to put a little switch to isolate your spots if you don't want them on under the bonnet rather than having to touch the inside of the car?

[KevinM]

The HID driving lights were all wired up using the Narva relay(diode protected) as per the circuit diagram and as soon as the battery was connnected, the main beam light on the right hand head light where I had drawn power from to connect to terminal 86 of the relay, lite up straight away, even though no lights were turned on and the switch was still in the off position. I had placed the switch between terminal 85 and the earth. So I moved the switch to between the main beam pick up and terminal 86. This stopped the main beam light coming on, but as soon as the switch was turned on (with no lights on), the driving lights came on but when I could not turn them off even when the switch was turned off.
I could not make the lights do what they were supposed to do.
I purchased a standard four pin relay and installed it and it all works fine.
All that I can think is that the diode protected relay was not the correct one.
Just thought I would let you all know that the Narva diode protected relay was not the way to go - well not the one I had.
Regards
Kev

[TheTree]

Kev,

Glad to hear you got it all hooked up and working finally despite the 5 pin relay fiasco !

Steve