Triggering Headlights and other Electrical (without motor)

I am wiring my new Headlights directly to the battery through two switched relays on my 1982 Seca.

My problem is that without my motor in the frame, I have no method to test all of the circuits for it, or my new LED turn signal electronic flasher.

What wire tells the headlights that the motor is running and gives them power? Can I "trick" it by applying 12V power?

 

Re: I need to trick my bike!

Upon further research this evening from the XJ CD's I believe I may have found my answer.

It seems to me according to the wiring diagrams for the XJ750RJ, there is a white wire running from the Generator to the Computer. From what I can tell this wire carries a 12V signal to the computer and tells it that the generator is turning at sufficient RPM to trigger the Headlights and other electrical items to function.

Does this make sense? If I hook 12V to this wire will this be the outcome I am looking for (ie headlights will light)? I hope that someone has experience with this as not being able to test items without a motor has become a frustration that I would love to overcome.

Thanks again
XJ750Guy

 

Re: Triggering Headlights and other Electrical (without moto

The wire you speak of carries an AC voltage when the alternator is producing.

On the non computer bikes this wire energizes the primary on the headlight relay when the alternator is producing electricity (and apparently very little as my relay usually activates while cranking, even if the bike doesn't start). The relay has an internal latch that feeds +12 volts to this input to hold the relay on even if the bike stalls or the alternator fails. The white wire to the headlight relay has a diode in it (in the diode block) that prevents the +12V from feeding back to the alternator. So on the non-computer bikes putting +12 on this lead will perform the function you are looking for.

Since the alternator is AC though I don't think the voltage on that wire is 12V. I don't remember enough of my electronics (Robert, where are you?), but my guess is it's less than half that. Depending on how the module handles that input putting 12V on it could cause a problem.

Since my relay engages while cranking I'd guess it takes very low voltage to make the circuit work. I'd try using a D cell with - to ground and + to that wire and see if that activates the circuit.

 

Re: Triggering Headlights and other Electrical (without moto

Thanks for the info Micarl.

When I got to work this morning I located the plug connecting the bikes main harness to the generator (3 white wires). In hopes of finding a solution, and unable to trace where they led, I jumped each wire, one at a time, to the positive post of the battery. This did power up the computer, and in turn the headlight, after the proper wire was found. The correct wire energizes the relay under the rectifier on the left side of the bike to send power to the computer.

I still however have not found a way to get the signals to function without the bike running. They will light but won't flash or function as they would if the bike was running.

 

Re: Triggering Headlights and other Electrical (without moto

Cool. I didn't see the relay in the diagram I looked at. I either overlooked it or was looking at the wrong diagram.

Not having a running engine shouldn't affect the signals. If it does, your battery doesn't have enough voltage under load. Also possible you have poor grounds or other problem connections.

 

Re: Triggering Headlights and other Electrical (without moto

My battery is fully charged and showing 12.8 volts, no problems there. Even before my teardown with the stock signals, flasher, etc, I don't recall being able to get the signals to flash unless the motor was running. The indicators would all light on the appropriate side (including indicator on dash) but not flash until the bike was running.

I have now replaced all the signals with LED aftermarket pieces with a 1.7 Watt per light draw. I have a Grote #44890 electronic flasher (1 watt min) in place and wired correctly. Now, when I turn the bike on with a direction chosen on the signal switch the indicator flashes once and then shuts off. It will not flash again until I turn off the key and turn it on again. With the stock flasher back in place it will light the signal and stay on as there is not enough current to break the flasher contact.

As it sits I guess I will have to just wait until I have the motor back in place and hope that they function correctly after the rest of the harness is hooked up. I just wanted to avoid any hold-ups once it was back in place so I could focus on tuning the mill.

 

Check the Alternator Brushes for Specs.

You need a "Load simulator" to get the lights to Flash.

Look on the website for SignalDynamics and see if they have one for your Bike.

 

Re: Triggering Headlights and other Electrical (without moto

I can verify that your turn signals won't blink without the bike running. On my xj750 Maxim the turn signals will come on but not blink if the engine is not running. However, they do blink on my xj550 Maxim (both '82 models) without the engine running. It's (my 750) still in project mode and I haven't gotten to the wiring yet, so it could be bad wiring or a signal control box on my bike.

I wrote the above paragraph about 10 minutes ago, but before I submitted it I went to compare the 750 signal control wiring to the 550 signal box. They both have the exact same wire colors and locations. I did not open the signal control box though, so they're could be something different inside.

So since my 550 will blink without the engine running, and the 750 will come on but not blink, I swapped the control boxes. Then I put my ignition into the on position, switched on a turn signal and nothing came on. So I put the original signal box back on and repeated the same steps, and now for some reason the turn signals won't come on as they did before.

But this did come on this way (still didn't blink, but they stayed lit). Try this:
1. Turn your ignition to the "off" position.
2. Switch on a turn signal using your handle bar control.
3. Turn the ignition to the "On" position.

This makes that signal light up, but no blink. Once I turn the blinker off, it won't come back on unless I repeat the steps again. Again, this is bike is still under project and is missing the front turn signals. And I know on my 550 the signals won't blink if one of the bulbs is burnt out. So this may be why mine will light up but not blink. Plus, the PO did a terrible wiring job, so this may not work for you (example: in the fuse panel, he hot glued a clip fuse into the main power wire to make it an inline fuse, I almost passed out when I saw that, so unfortunately my bike can't be used as an prime example). My bikes not in running condition yet, so I don't even know if they will even blink or not. Again, I know they signal lights blinked on my 550 without the engine running. I had to sacrifice the ignition switch and fuse panel box, or I'd try it on my 550 again to make sure, but I know for a fact they did blink. And before I did the control box switch, the signal lights would light up on my 750, but not blink with the engine turned off. I may have drained my battery a little to much though, because I tried to start it a couple times during the swap. But try the above steps. It's easy to do and worth a shot.

 

Start you restoration with the basics.

Get a high quality modern fuse panel in there and ... who knows??? ... you might solve some of your Electrical Problems in one fell swoop!

 

Re: Triggering Headlights and other Electrical (without moto

Rick,

I am a little confused by the combinations of posts on this thread. Are the turn signals on a 1982 Seca supposed to flash when the bike is not running, or just turn on and stay on?

The battery voltage is great and I have replaced the fuse panel completely with individual sealed fuses. Power is at least a constant 12V everywhere that I can check it without the motor in the bike.

I am replacing the alternator brushes as soon as my order gets here, but because the motor is not in the bike, I would assume this has no bearing here. I have an electronic LED flasher that requires virtually no draw to trigger, so I want to avoid a load simulator at all costs. I plan to use the power I save to guarantee good ignition system voltage, and power my new dual headlamps.

I have figured out how to trip the headlight relay so that the computer turns on and goes through its start sequence as well as making the headlights functional. I would just love to know what else needs power to make the signals act as if the bike were running.

 

You must have a light out or a bad Ground someplace. The Signal Lights should flash without the Bike running. If they don't ... and just come on and stay on ... there's not enough draw to trigger the STOCK Flasher.

If you replaced the Stock Flasher with a Digital Component ... the Turn Signal Relay isn't seeing enough juice to operate.
(This being the case on Bikes with a Yamaha self-canceling unit)

I think you have to remove the Self Canceling Unit for the LED's to Flash.
That, or you need to install a Load Simulator to have the Unit think its dealing with the right wattage for the Self Canceling Unit to complete the circuit and have the lights Flash.

I haven't dealt with any LED conversions. I TRIED to add a Unit that would Turn on my Rear Signals when the Rear Brake Light came on ... It didn't work because of the Self Canceling Unit being in the circuit.

I had to go OFF the Wiring Harness and rig a Relay to get the LED Type strips I added to the back of my seat for Brake Lights.
They come on after a relay in the Rear Brake Circuit closes to power them.

 

Re: Triggering Headlights and other Electrical (without moto

I had forgotten about the Self Cancelling Unit completely. Thanks for the reminder. I suppose to bypass it I will just have to take the "power in" wire and join it directly to the "power out" wire, but I'll have to tinker a bit to figure it out. My background in automotive hasn't prepared me for some a Yamaha's "fancy" wiring techniques! LOL

Thanks again for all the help Rick and Micarl!

 

Re: Triggering Headlights and other Electrical (without moto

Correct me if I'm wrong, but isn't the stock flasher control designed to stop the turn signals from blinking and will just keep it lit, if the either the front or back bulb on the same side is burnt out or missing.

Sorry if I added to the confusion xj750guy, I was just trying to help.

 

Re: Triggering Headlights and other Electrical (without moto

collinswj,

Please don't apologize for trying to help me find an answer to my questions! Especially not after taking the time to go out and physically check between your bikes. If my comments implied any ill will towards you, I apologize, and trust that none was intended.

I wish I had a second bike that I could compare to as now that mine is all apart it makes it more of a challenge to try to decipher than a complete unit would be. I even bought a complete wiring harness to use as reference, and have been using portions of it to keep wires of stock color when adding headlight relays, etc.

As far as your description goes of how the flasher operates, I agree and believe you to be correct. The flasher is simply a "closed" switch that "pops" open when a sufficient load builds, and then "closes" again after, restarting the process. The reason for my confusions is that my Seca flasher has never done that unless the bike was running. Now that I have changed my flasher to one using less load to "pop" it, as well as a great new set of signals, I would like to test them. This wouldn't be an issue if the motor was in the bike but it is not, hence, I will have to try "tricking" the bike by bridging the Self Cancel Unit.

Best Regards
Darryl

 

Re: Triggering Headlights and other Electrical (without moto

Then I retract my apology. I knew you meant no ill will, but I accidentally hijacked someone's thread earlier today, so I'm just trying to be careful not to do it again. My bike is in such bad shape, I think I have every problem posted today. And since mine weren't and still aren't flashing either, your post gave me a good excuse to delay me having to clean my carbs.

My issue has got to be either a wiring problem or the handle bar switch is malfunctioning, because my batteries showing a full charge and sometimes the turn signals will come on (and stay lit) and then I can try it again a few minutes (even seconds) later and they won't.

I know how confusing the wiring can get. If you have a digital camera or camera phone, just take a "before" picture when you're about to tinker with something. It's saved me a couple times.

 

Troubleshooting malfunctioning Turn Signals is a time consuming adventure.
I have seen:

Bulb Sockets oxidixed.
Bullet Connectors bad.
Wrong Light Bulbs used.
Burned out Bulbs.
Double Filament Bulbs instead of Singles
Lousy splices in broken wires.
Signals hooked-up backward --*
Burned-out Flashers
Wrong Flasher
Wiring hacked together and nowhere close to a circuit.

It takes time and energy to shoot an electrical problem.
All we can do for each-other is type.

And wish you good luck straightening out the problem!

 

Well I didn't want to start a new thread on this since it would pretty much be a waste. I saw a couple things mentioned in here that might help my own predicament.

My oil sensor wire isn't hooked up... Gotta find where that went to from the sensor. I only have the harness side of it. Second, and most important, I have no headlight or speedo light when the ignition is switched on, and turned over. Even had the bike running and nothing. The neutral light comes on. When I push the high-beam switch, the light dosn't come on on the panel. Also it is really hard to push. On top of this, theres a lone white wire at the rear of the bike that is unplugged, and there is nothing for it to plug into. I have every plug occupied, minus the oil sensor plug of course. All the harness in the front of the bike, and all relays and such are plugged in. I hear at least 2 relays click when the key is turned. Possibly all 3, or 4 whatever.

This is on a 550. My turn signals blink without the bike running as well. Also, I pulled the carbs off, cleaned out all the bowls, made sure there were no obstructions, and it doesn't leak gas anymore. But it still has an idle problem. Without choke, if I rev it, it revs to about 3-4k then very slowly drops down, and eventually dies right out. I did notice that the plungers didn't activate with the butterflies, but I'm not sure how that would work out while running.

Anyway, I mention the idle problem because I have a suspicion that it might be within the ignition module or something. Im also still on the tube style fuse block which is absolute garbage. On of the fuses is actually just a bolt, which is the main 12v power.

Anyway, back to the headlight speedo, would it be a headlight relay that may be gone? Where is it located? Is the front most relay, or second front? I know that the rear relay is for neutral safety, and at least one of the front ones switch over.

I'm on the verge of a complete teardown of the bike to figure out my wiring situation. And I really don't want to do it since I want this bike on the road this summer.

Thanks

 

Re: Triggering Headlights and other Electrical (without moto

Your first move is to excise that old fuse panel and install a new one. I can't emphasize how much that would contribute to your Electrical Problems.

Some of those old Fuse Panels "Look" just fine; but in reality they are near dead ... with the Fuse Holding Clips so weak or ready to break that there is such a resistance that the Circuits are weak or even open.

Once you get good power across all the Fuses, you'll be in better shape to shake-down and troubleshoot electrical problems. Right now, your Fuse Panel IS the problem and you can't go forward like that.

A very popular one is the 6-Place Fuse Panel from Wirewerks.com. It's only about $11.00 for peace of mind -- electrically.

http://wirewerksperformance.com/index.p ... 87ee7829ba

Change over to the Modern style of Fuse Block and go from there.

 

Thanks Rick. I've been looking to find the new style fuse block as the old one is way too loose and problematic. I've solved my problem with ingenuity, but found another problem. The harness that plugs into my Regulator has been chewed up on one single white wire. This has caused it to short out, so I will be in search of new connectors, and possibly a new regulator.

I've fixed my headlight problem by plugging in the blue/black wire from the main harness that bypasses the ignition going to the handle control, directly into the ignition harness connector. So now my headlight comes on with key on, instead of with firing.

It has solved that simple problem, and so far I have yet to find my oil level wire from underneath the bike. I have locate the wire that comes from the gage light, but the one from the sensor has decieved me.

Anyway, sorry to jack your thread, but I figured this was an appropriate place.

Also, I came across a free PDF service manual download, which has helped tremendous amounts.

This is the main page with all Yamaha bike manuals. Find your respective model in those pages http://pdftown.com/Pdf-eBook/Yamaha.html?from=10