Electrickery question

Paul LeClair

Paul LeClair

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Calgary, Alberta, Canada
Not Laverda related, but a question who understand dc circuitry.

Google and AI are dangerous.... Both assume I have more knowledge than I do.

On my 2022 Kawasaki H2 SX SE I have mounted two pairs of high output Denali D2 LED driving lights, and a "Data Dim" controller.

I have all the circuits figured out EXCEPT having the two pairs of driving lights go to highest level of output automatically when I switch the headlight to high beam.

The issue is from the trigger signal from the Kawasaki headlight. I have run a single trigger wire off the high beam. The Denali light controller is expecting to see NO voltage when the high beam is off and 12-14 volts when the high beam switches on. My problem is that the high beam circuit always has running DC voltage of 14.2 volts while the high beam is OFF. Strange, but stranger is that when the high beam is switched ON the high beam circuit has a DC voltage of 39.5 volts. I checked with Kawasaki, this is "normal".

So, I need to add to the single trigger wire from the headlight to the Denali light controller something that blocks, say. everything below 15 volts, to zero, but reduces the 39.5 volts to, say 20 (?) volts or whatever will not fry the Denali light controller. I have gone down the rabbit hole trying to figure out DC op-amp comparators in IC form, but the basic one I found LM3111 has an upper limit of 36 volts. Frankly I am lost. Denali does not seem interested in figuring out the issue in relation to such a low production number motorcycle....

if I knew what I was doing I suspect this should be fairly simple, on the signal trigger wire block to zero everything below say 15 volts, and allow say half of the 39.5 volts to pass through to trigger the full intensity of the LED driving lights when the bike high beam is switched on.

Anyone?

On a Laverda related note, the snow is mostly melted here, I spent today changing oil and brake fluid on all three Laverda triples, firing all three up, and short warm up rides on each of the three. Clutch plates are dragging a bit on one of them which I am sure will be remedied by a longer and harder ride. All three are a bit dusty from winter storage, a good cleaning is in order in the next while. The 79 1200 really barks with the recent full chrome exhaust system from Malcolm Cox, beautifully made, great fit.

Paul LeClair
 
Ooh, an electrickery brain teaser. Sounds simple enough to sort out, but can you confirm a couple of things first ...

I've not come across higher than 12V headlamps as original fitment on a motorcycle before. I'm wondering if the 39.5V Kawasaki high beam feed to the headlight is AC straight from the alternator (incandescent lamps work ok on AC).

While I'd have to look up the specs for the Denali LED, I expect it needs a DC feed.

I don't reckon you'd need to muck about with opamps or any other fancy electronic wizardry. I expect it can be done with a simple relay and possibly a little signal rectifier if AC is involved. I'll see if I can find a wiring diagram online for the Kawasaki H2 SX SE and get back to you.
 
Hi Cam I just took delivery of the factory service manual for the 2022 - 2023 H2 SX SE, considerable changes to the bike as of 2022 from the earlier versions like the 2018 I had. I will scan the wiring diagram and send it to you.

The Denali driving lights need DC trigger voltage, no voltage to the single trigger wire when high beam is off, running trigger voltage 12 - 14.5 to the trigger wire when high beam is on, could maybe use even higher dc voltage as a trigger but will need to check. No idea if the 39.5 volts is AC, I measured it with a digital multi meter set on dc. The stock headlight is really bright, way brighter than on the pre 2022 bikes.
 
Had a quick look at the 2024 Kwaka, possibly there is onboard CAN based chassis communications, doubt yours Paul will be HID headlight, though have no certain knowledge. Certain CAN systems have a dc buss ( 2 wire ) and data comms imposed onto the DC buss, this could ( again never certain ) introduce an high frequency AC component being read by the meter in use, DMM have different ways of measuring and therefore response reading can vary markedly. My suspicion is that the onboard control is not a old style DC level control, not sure that helps, would urge caution all the same, does not take a lot to take out a CAN buss driver chip or chips, RS485 is not all that rugged to external voltage gradients. j
 
If your uncertain on how to custom wire it and cant figure it out...it was so simple in the old days....is there a chance another Kawasaki like the Concours has factory optional accessory lights and you could order a plug and play harness kit. Or check for Forums on other Kawasaki models where guys would be more inclined the add lights and see if they have to deal with this setup as well.
 
Some modern cars and bike use headlight bulbs with only one filament in the bulb. To make the bulb be on high beam or low beam, they pulse width modulate the current going to the bulb.

This can make reading the voltage on the wire to the bulb difficult. What voltage do you see with your meter set to AC?

Now as your bike is a 2022, I am guessing it may have a LED headlight?
 
I had a quick look at a Kawasaki wiring diagram online. I came away knowing less about how the bike works than before I looked at it! It's fiendishly complicated and most functions of the bike are controlled by the ECU, which does have CAN based comms as John suggested. The ECU has 3 multi-pin connection plugs with a total of 80 inputs and outputs. If it was my bike, I'd be reluctant to fiddle with any of that stuff.

However, I looked through the list of items controlled by the ECU, and headlights isn't among them. So you might be OK to mess around with the light switching.

In your latter post (#4), you talk about a trigger voltage for the Denali light. If it has a supply voltage and a trigger input, it sounds as if it has its own built-in solid-state relay. I'll see if I can find any info on the Denali system online.

I'll spend a bit more time peering at the wiring diagram to figure out the light switching.

I can't help wondering why you're swapping the light when you say the stock headlight is very bright.
 
Dellortoman said:
I had a quick look at a Kawasaki wiring diagram online. I came away knowing less about how the bike works than before I looked at it! It's fiendishly complicated and most functions of the bike are controlled by the ECU, which does have CAN based comms as John suggested. The ECU has 3 multi-pin connection plugs with a total of 80 inputs and outputs. If it was my bike, I'd be reluctant to fiddle with any of that stuff.

However, I looked through the list of items controlled by the ECU, and headlights isn't among them. So you might be OK to mess around with the light switching.

In your latter post (#4), you talk about a trigger voltage for the Denali light. If it has a supply voltage and a trigger input, it sounds as if it has its own built-in solid-state relay. I'll see if I can find any info on the Denali system online.

I'll spend a bit more time peering at the wiring diagram to figure out the light switching.

I can't help wondering why you're swapping the light when you say the stock headlight is very bright.
Click to expand...

Fucken things go faster than the light source distance. That’s probably why.
 
OK, I've had a bit of time to absorb the wiring diagram and I think I can point you in the right direction. I thought about taking this discussion off line and just do it via email rather than clog up the Laverda forum with Kawasaki stuff, but maybe it's a better idea to do the basics on here so it can be peer reviewed by the many people on here who are smarter than me. I could be missing something important.

There's no AC connection from the alternator to any of the bike's systems. Everything goes via the R/R so it's all DC.

Low beam is supplied with battery voltage (12V) wired via a relay that activates when the ignition is switched on.

High beam is a little more mysterious. The dimmer switch provides an on/off toggled ground signal to the instrument panel (called "meter unit" on the Kawasaki diagram), which obviously houses some kind of control system. What actually goes on inside the meter unit is not shown, but there's a 12V supply from one of the bikes fuse boxes which apparently provides power for multiple functions.

There are also two CAN BUS connections to the meter unit (CAN high and CAN low, which go all over the bike). CAN is an acronym for Control Area Network and is a system by which the various electronic nerve centres of the bike communicate. What they're actually saying on that comms network is beyond my knowledge, but I'd guess a whole lot of data are shared between various control units.

Anyway, an output wire from the meter unit goes directly to the high beam lamp. If you hadn't said it's 40V, I'd have assumed 12V. Evidently there's some kind of voltage step-up system inside the meter unit, which isn't identified on the wiring diagram. Incidentally, it could still be AC, depending how the voltage is stepped up.

The bottom line is that you need a signal to switch the Denali lights on. You can take that signal from one of two places using a relay to switch it:

1. The dimmer switch on/off ground toggle. You feed power to the relay coil, which becomes energised when the ground is connected. The only question there is which way does it toggle? Is high beam activated when the signal is grounded or not grounded? The simplest way to find out is to put a meter on the dimmer switch to see what it does, then wire your Denali light signal via the NO or NC relay contacts accordingly.

2. The 40V feed to the high beam light. You could connect a signal wire from the high beam light supply to operate the relay coil. I'd guess you'd have difficulty finding a relay that works with a 40V signal, so you'd probably have to use a series resistor to reduce the voltage getting to the relay's motor coil. I don't know whether tapping into the 40V cable will upset the CAN network or some other sensitive system.

I think option 1 is the simplest and safest. You don't have to mess around with anything higher than 12V or possible AC systems, and you're unlikely to bother any of the intelligent systems on the bike. The ground signal wire you're looking for is red/black and goes from the left switch housing to the meter unit (instrument panel). Just fish out that wire and check its operation. It should switch to ground when the dimmer switch is operated (one way or the other). If you're unsure how to wire the relay from there, I can do a simple wiring diagram for you.
 
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Firstly, I would have less than 5% of the knowledge of Cam and Jon regarding electronics. Nevertheless I'm not convinced there is true 40V in the system. Are you using a high impedance multimeter Paul?
 
Expanding on Cams dedication sublime, grin. CAN is the transport protocol and associated packet assembly disassembly structure, the actual ( modules interconnect ) line driver stage is based on older RS line drivers and voltage standards. RS422 and RS485, single and multidrop hardware drivers and receivers, as a guide. Alternate composites notwithstanding. In the case of a square box on a schematic, could be multiplexed input ie not a static switch arrangement, or you can control 4 devices with 2 wires so on with binary control encode decode arrangements.

CAN can also have closed loop control incorporated, ie a signal is sent out and a return validation signal is scanned for. Toyota COP system is an ignitor on coil for each spark plug, the ignitor has valid return signal wire conformation for the ECU to validate. Why the local workshop had no clue when the spark plug failed yet the COP electrical system said no fault with the ignition, mechanic(s) can be slaves to OBD codes. There could be closed loop control on headlights, long call though very real these days of vehicle electronics.

Witnessed damaged control systems by tapping into control wiring assuming that is was a simple dc control arrangement. Somewhat a prophet of doom..... years on repairs have me so.... beware the wiring loom that entices.... does not take much to ramble...j
 
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Following on from Bruces' reply. Mine not exactly germane, post here a type of control that is part of modern technologies. Specious assertion that the mosfet will failsafe to short... sales talk and not accurate. Note the reference to CAN Buss for bimmers... j


Also note the operataing voltage range on this type of headlight ( up to 30V ) in the description paragraph

 
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Blimey John. You've lost me with your explanation of CAN Bus systems.
RS numbers, single and multidrop, multiplexed inputs? I know when I'm outta my depth. :confused:
I like simple electric circuits, positive and negative wires, Ohms Law and stuff like that.
 
chrisk said:
Fucken things go faster than the light source distance. That’s probably why.
Click to expand...
ChrisK nailed it.... While the stock headlight is very bright, I have also fitted two pairs of Denali D2's driving lights. One pair with yellow lens filters. The other pair clear. All four are fork mounted, the clear lower pair on the fender mount, the yellow lensed upper pair on the inverted upper fork leg. The four lights combined seen coming is sort of like a ridiculously quickly approaching UFO. That is the point of the exercise. Closing speeds are potentially so high I want to be noticed.....

I successfully wired the Denali light controller to the horn. Press the horn button and all four driving lights go to full high and also strobe furiously, can't be missed. Only issue is blinding whoever is looking at them when they strobe. I also fitted the Denali "Sound Bomb" horn, ridiculously loud.
https://denalielectronics.com/products/d2-led-light-pods-with-datadim™-technology. The four pairs are also wired to the turn signals, apply the turn signal and the yellow lensed driving light flashes with the turn signal on the bike and the lower clear lensed light on that side goes off during the duration of the signal being on. Very conspicuous.

Thanks for all the knowledgeable comments and analysis. My take away is I may be at risk of frying something in the very complicated electronics and that I am way out of my depth. I think I will leave the high beam function alone.

I really appreciate all the help, thanks so much!!
 
Dellortoman said:
Blimey John. You've lost me with your explanation of CAN Bus systems.
RS numbers, single and multidrop, multiplexed inputs? I know when I'm outta my depth. :confused:
I like simple electric circuits, positive and negative wires, Ohms Law and stuff like that.
Click to expand...
Not at all Cam, much worth in the efforts you applied to Pauls modification prospect. Well reasoned how you actioned the task at hand. Some guidelines from the sidelines, ( never be a poet ), to avoid unexpected misoperation or damage. j
 
Those Denali lights are nifty little gadgets Paul. It still amazes me how bright LEDs are these days. I remember when they were dim little things only good for dash warning lights.

I don't reckon I'd bother fitting any fancy lights to a bike though. I try to avoid riding after dark. That's when all the animals come out on the road in Tasmania. Most of our native fauna are nocturnal. I even try to avoid driving my car at night on country roads. I'm not so much worried about animals damaging the car, but I don't want to damage the wildlife. I love our native animals and it saddens me to see them squashed on the road.
 
Dellortoman said:
Those Denali lights are nifty little gadgets Paul. It still amazes me how bright LEDs are these days. I remember when they were dim little things only good for dash warning lights.
Click to expand...
A mate of mine bought a second-hand Ducati parallel 500 twin (GTL 500?), it used 3mm LEDs on the dash panel. Very advanced technology for the day but they were very hard to see in daylight.
Likewise I am still amazed at the progress in LED technology over the past 50+ years.

bazzee
 
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