Ignition coil power wire?

db-89

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I need an ignition impulse for a trailtech voyager and they recommend going from the coils + input. Does anyone know which pin on the left cylinder primary coil is this one?

Thanks
 
I need an ignition impulse for a trailtech voyager and they recommend going from the coils + input. Does anyone know which pin on the left cylinder primary coil is this one?

Thanks

The pin you need is #1. Center is gnd., while 1 and 3 are + and ignition signal. If you want to measure it, make sure to use a digital voltmeter as they put less strain on the input.

I would be utterly careful tapping into the coils on your bike. On a regular coil, the + input is capable to handle several amps. On engines with integrated coils, the coil + input is supplied by the ECU, and we have no way of knowing how much power it is able to handle.
If the trailer needs this + input for a high resistant control input only, there ought not to be a problem. But if it is meant as a supply voltage I would suggest to look elsewhere.
If you need some sort of speed signal, the center pin on the GPS plug supply 6 pulses for each turn of the rear wheel, so there are several ways of doing it.

Generally, I would be VERY CAREFUL tapping into any signal or wire that is supplied from any computer on the bike.
 
Are you after an actual voltage to trigger your bit of kit, or just an inductive pulse

If the latter then you should be fine, as your not actually breaking into the curcuit, more passively looking for a spike, and using that as a signal.

if the former, then as Knutk say be very careful
 
Just had a look at the Voyager manuals -

They use simple wrapped wire passive induction to detect the spark on the HT side of the coil

Unfortunatly the GS dosent have a seperate coil & lead assembly - it has an integrated coil & cap assembly

As you say taking a feed from the positive side of the coil may be possible

To do that you would need open the harness before the coil connector and wrap round the positive wire.

However i dont think the low tension +12v will generate a big enough pulse to trigger the voyagers electronics

If you look at the manual its round the plug lead itself

plug leads typically carry 12K-25K and can in some cases got to 45K volts

if it needs that sort of voltages to trigger an inductive pulse i doubt going of the low tension side of things will work
 
Just had a look at the Voyager manuals -

They use simple wrapped wire passive induction to detect the spark on the HT side of the coil

Unfortunatly the GS dosent have a seperate coil & lead assembly - it has an integrated coil & cap assembly

As you say taking a feed from the positive side of the coil may be possible

To do that you would need open the harness before the coil connector and wrap round the positive wire.

However i dont think the low tension +12v will generate a big enough pulse to trigger the voyagers electronics

If you look at the manual its round the plug lead itself

plug leads typically carry 12K-25K and can in some cases got to 45K volts

if it needs that sort of voltages to trigger an inductive pulse i doubt going of the low tension side of things will work

Voyager themselves say to go to the coil posative and to directly wrap around it.i tried last night and no activation.tbh i think my one could be fucked , its a pity because they're a great bit of kit
 
Voyager themselves say to go to the coil posative and to directly wrap around it.i tried last night and no activation.tbh i think my one could be fucked , its a pity because they're a great bit of kit


Try it on a car or bike with seperate coils / leads it may work ..

It does need to go to the poisitive side of the coil, but i think you will find it's the HT side not the LT side
 
I have never performed a reading on the voltage level on ignition leads on this bike.
However, generally speaking, as both wires (the third one is gnd.) are routed directly to the ECU. As the ECU is a computer, keep in mind that the worse thing you can do to a computer is throwing spikes of voltage to it. I think you may expect that what ever spike there may be generated in this cable, the spike will be suppressed in a very efficient way in order to protect the ECU.
I think it may be time to search for alternate solutions.
 
I took the time to download the manual for the Trailtech, and they suggest you wind the ignition pickup cable around the coilbody. In the BMW it's a tight fit, but it may work...
 
I took the time to download the manual for the Trailtech, and they suggest you wind the ignition pickup cable around the coilbody. In the BMW it's a tight fit, but it may work...

I looked at that,

The cap on a plug lead is surpressed to prevent RF spikes and flash over from the plug its self

Would you want to take the risk of potentially frying the unit or worse?
 
I looked at that,

The cap on a plug lead is surpressed to prevent RF spikes and flash over from the plug its self

Would you want to take the risk of potentially frying the unit or worse?

I'm merely referring the Trailtech manual.
Apparently the pickup of the signal is based on inductive transferal only. I don't know how the Trailtech is made up internally. However, since they suggest it, the risk ought not to be overwhelming ?
 


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