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I have an 2005 NC series 1, and I'm trying to install a set of aftermarket driving lights.

These lights - 55W Narva 4 inch spotlights - were previously installed on my last car (a 1995 Toyota RAV4), connected to the original high-beams using a relay; the positive lead on the original high-beam triggers the relay, which in turn closes the neutral side of the circuit on the Narvas and - hey presto - let there be light.

I've now connected these lights up to the Mazda in the same fashion... but I've found that on my Mazda, the existing high-beams have 12 volts power running to them whenever the low-beams are on. Even when the bulbs aren't lit up, they still have 12v to the positive pole.
As a result of this, the Narvas come on with both the high-beams AND the low-beam lights - which I don't want. Que curioso.

On the RAV, the high- and low-beams were both within the same bulb, but with two elements. On the Mazda, the high- and low-beams are separate light bulds, in separate (for lack of a better word) housings.

I rang an auto electrician this morning, and he informed me that some of the newer Japanese cars have weird switching like this. However, he wasn't prepared to go in to any more detail unless I gave him an unspecified sum of cash.

So... does anybody out there have any ideas on how I can resolve my problem? I want the Narvas to come on with the Mazda high-beams (which they do), but to turn off when I switch back to low-beams (which they don't).

Thanks in advance.

They apparently have a negative switching system, but sorry no idea on how to set it up?

Had a play and my Theory wont work so I have deleted it!

It is normal to have a switch- just like the fog lights. I would say you can use a switch inside the car to break the circuit. I do not think this will give you exactly what you want but you may still want to be able to switch the driving lights on or off even with the high beam, still activated- I have that facility on one of my cars.

The other thing you can do is contact Narva and ask for a solution. It is normal that the big guys like Narva ( Brown and Watson) head office Ferntree Gully have auto elecs on the payroll who will give you safe advice.

Will be interested to know how you get on.

Mr Morlock wrote: The other thing you can do is contact Narva and ask for a solution. It is normal that the big guys like Narva ( Brown and Watson) head office Ferntree Gully have auto elecs on the payroll who will give you safe advice.

Will be interested to know how you get on.

Agree

Many thanks to everybody for coming back to me!

I'll be installing a switch in the dash as well, which will allow me to turn the driving lights on/off independant to the factory high-beams. However, given how I use the driving lights, I would prefer this be in series with the factory high-beam wiring (instead of having them a separate circuit); essentially, for the driving lights to come on, the high-beams MUST be on, and the dash switch must be closed.

I googled 'negative switching', and there are enough similarities that it looks fairly likely that this is what Mazda have done. I found some really helpful wiring diagrams, and I'll tackle this again over the weekend. I'll let y'all know how I go.

FYI... This issue is a fairly common thread on the 4x4 forums, and almost exclusive to Toyota 4x4s - but obviously, that wasn't the first place I'd have thought to look. Funnily enough, I never had this problem when I installed them on my Toyota 4x4!

Thanks again to everybody who came back to me. I've tackled this again over the weekend... I've got my Narvas working now, so I'm posting this our of courtesy to anybody else who wants to tackle the problem.

And let me tell ya... geez, as much as I love my Mazda, I'd love to know what the hell they were thinking when they came up with this.

From factory, there are two leads running into the back of each high-beam bulb. For the sake of the solution, I'll call these (since they both carry 12V) 12A and 12B. I'd recommend using either a voltmeter or one of those proby-lightbulby-screwdrivers (technical term) to work out which one is which.

12A carries a constant +12V current to the high-beam bulb.
12B changes voltages depending on where the lights are set;
When all of the lights are off, or with JUST the parking lights on, this wire carries zero voltage
When the low-beams are on but the high-beams are off, this wire carries +12V, even though the high-beam bulb does not come on
When the high-beams are turned on, the current on this line drops back to zero volts

Now, to hook up the driving lights, connect your relay in this fashion:

Pin 30 connects to a fuse holder, which then connects to the +12V on the battery
Pin 85 connects to 12A (detailed above)
Pin 86 runs to a new switch I've installed in my dashboard, which then connects back to 12B (detailed above). That's right, it runs through the firewall twice
Pin 87 connects to the positive lead on the new driving lights

It's stupid and and I hate it and it makes no sense at all... but it works.

Ciao for now!

Glad you fixed it!

Just as an aside, legally, driving lights can ONLY come on with your high beams.
If you wire them through an independant switch, and they are able to be turned on without high beams being activated, you are beaking the law and many cops will test them to see that they can't come on without high beams.

I was tested for this many years ago when I used to have aircraft landing lights mounted on a couple of my cars.

Mind you, legally, fog lights should only come on with parking lights and when you switch to your main beams, they should switch off, but no-one seems to care about this, although you could be booked for it.

the wiring of fog lights is defined by OE fitment ie there are numerous models which are fitted with fog lamps as either an option or as standard. The sellers/ manufacturers are obliged to sell them to legal requirements insofar as operation is concerned. I cannot think of any volume car being fitted with driving lamps as standard .

Benny wrote:Glad you fixed it!
Just as an aside, legally, driving lights can ONLY come on with your high beams.

I was aware of that... the extra switch I connected up (the one in the dash) is in series with the relay for the driving lights. This means I can turn the factory high-beams on without the driving lights coming on, but not vice-versa. So it's all good.

Mr Morlock wrote: I cannot think of any volume car being fitted with driving lamps as standard .

The one that leaps most readily to my mind is the Ford Mustang. A couple of the standard Ford models come with them (mounted in the grill, just near the headlights), plus the Roush and the Shelby-tuned ones have them.
But since the Mustang is a) not available out here as a mass import, and b) American rubbish, I'm not sure if it counts.

Speaking of which... I was on a drive with a group of the MX5 guys lately, and one of them noticed my spotties. He says to me "I like your lights... [your car] looks like a little Mustang!"

Mr Morlock wrote: I cannot think of any volume car being fitted with driving lamps as standard .

GT Falcons. (Several models)

The latest model GT Falcons have bumper mounted fog lamps not driving lamps. The twin headlamp config normally is low beam and high beam. Modern lamps employing reflectors usually have such a good high beam that most drivers would never need a long range driving lamp.