Canbus headlamp aux. Circuit trigger

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John_Galt

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Mazda's cx30 steering/adjusting led projector lamps are very neat, but after driving mine cross country recently, I felt they were lacking a bit in center punch. The highbeam is a very tall, very broad beam, which was incredible driving through the tetons, but in the wide open they were not.. comfortable to drive with.

The fusebox has two 15A fuses indicated for each the driver/passenger side lamps. It appears one feeds both the low and highbeam on that side, while the other feeds the turn signals/front markers and the servos to aim and adjust the lamps. There does not appear to be a separate circuit to tap to wire a relay to trigger the highbeams. This vehicle is also not equipped with fog lamps, where my other plan of attack would be to use a relay that could activate an aux circuit when the fog circuit loses power.

I have found two possible solutions, the CanM8 'cannect,' and the XBB 'Lightswitch.' But I don't know anyone who has used either in any other vehicles, and I don't want to risk damaging a new vehicles electronics.

The CanM8 does not list the cx30 as a compatible model. However the cx30 is based off of the 3, which is. In the installation instructions page, it also says that it uses two wires to connect to the Can Lo and Can Hi circuits. So this does not appear compatible with the CX30.

Similarly the XBB lightswitch appears to need a signal wire to trigger. They do offer an OBD2 interface "dongle" that is supposed to "learn" what the high/low circuit trigger is and the communicate wirelessly with the lightswitch unit. My concern with this would be the possibility that it interferes with the vehicle in some way.

Is there another way/product that can be used to trigger a relay circuit in some manner?
 

-Virgil-

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My concern with this would be the possibility that it interferes with the vehicle in some way.

I would have that exact same concern, aside from the usual ones (will it work correctly...not just this time, but every time?). With that said, this other XBB product, the Dongle, does list the CX-30 with adaptive LED headlamps on its compatibility list.
 

John_Galt

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I will have to see if there is a US distributor for the dongle, given the current lead times with international shipping. $210 + shipping is steep, but ultimately worth it *if* it works well and causes no issues.

As far as the headlamps themselves go, I saw the IIHS had the base models (non-adjusting) lamps rated good, but the higher trims with adjusting lamps rated poor. As I believe they use the same projector setup, would the ratings difference potentially have come from a difference of aim from the non-steering lamps, or is it more to glare to oncoming traffic. It was very interesting to observe the low beam cut off be raised and lowered as I approached vehicles in the dark.
 

-Virgil-

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Looking at the IIHS test results, specifically looking at the system rated Poor, we see really excellent, long low and high beam seeing distances, but truly excessive low beam glare (+133%, +79%, and +52% of the threshold intensity, at various angles). This suggests the lamps were aimed too high from the factory.
 

ameli0rate

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My aging Volvo (2006) has a pigtail under the front of the car for driving lights. It's activated by adding an OEM driving light switch, which talks to the CANbus and tells it that it's for that pigtail.

It might be worth digging into some factory options - could it be optioned with driving lights? - and see if it might be pre-wired for it, after all. With so many people around the world driving in dark forests and the like, I'd LIKE to think that something as common as driving lights would be pre-wired.
 

John_Galt

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I'm fairly certain that most vehicle manufacturers would not waste the copper to add something so niche. Especially on a small crossover, not a vehicle that most would ever consider adding lights to. It's interesting that volvo had that option, though. Is yours a US domestic market model, or are you located in europe? I see lots of older scandinavian volvos with large auxiliary lights online, I suppose being that far north they deal with extended periods of darkness that make them necessary.
 

LEDphile

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I'm fairly certain that most vehicle manufacturers would not waste the copper to add something so niche. Especially on a small crossover, not a vehicle that most would ever consider adding lights to. It's interesting that volvo had that option, though. Is yours a US domestic market model, or are you located in europe? I see lots of older scandinavian volvos with large auxiliary lights online, I suppose being that far north they deal with extended periods of darkness that make them necessary.
There's a balancing act between the cost of the additional materials to support options that may not be populated, and the cost of having multiple part variants to support the options (and this includes the cost of managing the differently configured vehicles along the production line). Things get even less clear once dealer-installed options come into play, as the costs to swap out a wiring harness may be significant.

So for dealer-installed options, at least, there's a high probability that the connections are present in the factory wiring harness to support them. And for factory-installed options on a modern vehicle, it's probably a 50/50 guess.
 

-Virgil-

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My aging Volvo (2006) has a pigtail under the front of the car for driving lights. It's activated by adding an OEM driving light switch, which talks to the CANbus and tells it that it's for that pigtail.

Are you sure it's for driving lamps (supplemental high beams), not for fog lamps? They aren't the same thing.

It might be worth digging into some factory options - could it be optioned with driving lights?

Very few vehicles come with (or can be ordered with) driving lamps in most markets.
 

Alaric Darconville

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My aging Volvo (2006) has a pigtail under the front of the car for driving lights. It's activated by adding an OEM driving light switch, which talks to the CANbus and tells it that it's for that pigtail.
My '01 Corolla has them for *fog* lamps. It takes replacing the combination switch and adding a relay (and the lamps themselves). It's not very likely yours are for auxiliary high beam lamps-- especially if the pigtails are under the car instead of by the grille. (Many bulb sellers refer to fog lamps as "fog/driving" lamps because it's just easier to attract buyers who don't know the difference themselves.)
 
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