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Discussion Starter · #1 · (Edited)
Hello guys,

I've read all the threads regarding the 'no spark' subject.

So the story is that my I rode the SV with a bad R/R (overcharging) and it died on me.

I checked the connections, everything is in order, except for the orange/red wire at the ignitor.

I jumped it with the 100 Ohm resistor but I can't read (5, 7) volts there; it's only about 0.8 volts - This happens only with a good working ECU (with the original ECU, the reading's 0 - maybe this could be a quick test of the ECU?)

So in the ECU connector I have:
  • 190 Ohms from the pulse generator;
  • 12V on ECU power wires
  • 100 Ohms on the anti-theft system (jumped it)
  • 0.8V on the anti-theft wires (it doesn't matter where I ground, still the same reading)

What I might have missed (from other threads, not yet checked):

  • "Before throwing in the towel, you might check the ground between the battery and the Black/White wire at the ignitor. Probe B/W as close to the ignitor as possible to include the full wire. Resistance should be well under one ohm. Voltage drop on the same path (with power on) is a more accurate measurement and should read close to zero volts, maybe a few tens of millivolts."
  • Signal generator if it's grounded;
  • "Follow the negative wire from your battery, it connects to your motor near the bottom on the 2nd cylinder, remove the lug, clean it up nice and replace"

I checked for a spark visually and have no luck :|

On the bright side, I've learned so much these days.

Do you guys have some ideas as to what further I should check?
 

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Raul, does your bike have the stock ignition switch? If so, an external, “jumped”, 100ohm resistor is not necessary and can actually cause no spark.
 

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Discussion Starter · #4 ·
The bike has the original ignition switch. But the thing is, at the back of the connector, I didn't have 100 Ohms, although I did have 100 Ohms measured at the green ignition switch connector (also, with the original setup and with jumped 100 Ohms, same 0.8V). I figured the wire is somewhere interrupted and can cause a problem; that's why I jumped it. In order for the switch to not be a problem (to be jumped maybe?), what else should I do?
 

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Discussion Starter · #5 ·
OK so today I tested the coils by jumping the ground wire from the ignitor directly to the coils and I had a spark.

I also tested the harness (ground, from ground ignition unit to battery) for resistance - it's 0.8 Ohms.

The signal generator isn't grounded.

The ignition unit is grounded directly to the battery - from the battery, I did two wires - one spliced on B/W wire and one with the 100 Ohms resistance that goes to O/R wire in the ignition unit (the wire is cut, it's battery -> 100 Ohms -> ignition unit connector; doesn't go "back" to the ignition switch).

At this point, I'm thinking that the ignition unit is also fried, although I bought it from someone who's trustworthy.
 

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... the thing is, at the back of the connector, I didn't have 100 Ohms, although I did have 100 Ohms measured at the green ignition switch connector.
So measuring at the ignition switch connector (while unplugged from the harness), the 100 ohm resistor tested good? The other connector you are talking about, is that the connector down at the ignitor? If so, when measuring at the ignitor connector (with the ignitor unplugged), you did not see 100 ohms? That would mean there is a wiring error, but that would be unusual. Maybe double-check.

Here is the minimal circuit needed to get spark. If you are bypassing the 100 ohm at the ignition switch with an external resistor, follow the below circuit exactly. It is important that there is only one resistor in the circuit.
Product Rectangle Schematic Font Parallel
 

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Discussion Starter · #7 ·
"So measuring at the ignition switch connector (while unplugged from the harness), the 100 ohm resistor tested good? The other connector you are talking about, is that the connector down at the ignitor? If so, when measuring at the ignitor connector (with the ignitor unplugged), you did not see 100 ohms? That would mean there is a wiring error, but that would be unusual. Maybe double-check. "

- my mistake: i was talking about the connector down at the ignitor, you are right.

I'm confident that this piece of harness is exactly like in the race harness.

I have another concern regarding the ignitor connector; maybe somehow it got bad with all the measurements? Should I try to bypass it somehow?
 

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... I tested the coils by jumping the ground wire from the ignitor directly to the coils and I had a spark.
That proves the ignition coils, coil power, high tension leads, sparkplug caps, and sparkplugs are good.

That leaves only the ignitor, pulse gen, and the 100 ohm resistor.

Going back to the beginning. Did the bike die on you while riding it? Did you have to get towed home? Is the bike 100% stock, no wiring mods?
 

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Discussion Starter · #10 ·
Thanks for the patience of reading & answering :)

The bike died while riding it, yes. I got towed home, yes. The bike doesn't have stock harness, it has been tempered with, unfortunately.

I used two pulse generators (with stator & cover, the whole assembly), both of which have good voltage & good resistance. I wired them directly to the ignitor. Can they be dead with good electrical readings?

About the 100 ohm resistor: at this point, I have 100 ohms resistance where I should have it; even the voltages are good - 5 volts (ignitor) connector unplugged, 0.8 volts connector plugged. I think I will reconstruct the original orange/red wire, because it's the same result (ohms, volts unplugged, volts plugged) as the 'shorted' version with the resistor.

Is there any possibility that the ground wires that go from ignitor to both coils are bad? I'm also thinking about this...
 

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... at this point, I have 100 ohms resistance where I should have it; even the voltages are good - 5 volts (ignitor) connector unplugged, 0.8 volts connector plugged.
The voltage on O/R should be about 5v with the ignitor plugged in and with the resistor connected. If O/R is 0.8v, something is wrong.

Can you post a photo of the wiring? That might help.
 

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For sure those voltages are incorrect for the gen2 SV. The gen1 SV anti-theft circuit is opposite polarity but I believe the voltage on O/R for gen1 should be similar, ~5v with the ignitor plugged in.
 

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Discussion Starter · #14 ·
Hello,

So I had some time yesterday afternoon and I have some readings. I posted an album with them and with some other pictures.

My main questions become:

  • Is it normal to have 0.3 Ohms resistance between battery negative terminal and the rest of the grounds with ignition off AND 6.3 with ignition on?
  • What's the correct voltage of the O/R wire? I have 0.78 either with the original switch setup or with the 100 Ohms resistance grounded. The same exact value.
  • Is it normal for the meter to show different values when switching the positive and negative probes between them? (6.3 Ohms with red pole at ground and black pole at battery negative terminal versus 0 Ohms with black pole at ground and red pole at battery negative terminal)

Motor vehicle Automotive tire Gadget Audio equipment Hood
Motor vehicle Hood Automotive tire Bumper Automotive exterior
Motor vehicle Light Automotive tire Bumper Automotive exterior
Motor vehicle Bumper Automotive exterior Hood Automotive tire
Motor vehicle Automotive tire Gas Automotive exterior Auto part
Motor vehicle Light Bumper Audio equipment Electronic engineering
Motor vehicle Automotive tire Bumper Automotive fuel system Electrical wiring
Electrical wiring Cable Electrical supply Wire Electronic device
Motor vehicle Hood Automotive lighting Automotive tire Electrical wiring
Motor vehicle Hood Automotive tire Electrical wiring Bumper
 

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Discussion Starter · #15 ·
I also thought to make a minimal required harness and to test out like this:

Rectangle Slope Parallel Font Number


With an external battery, with the coil assembly taken out of the bike.

If I have spark, that means the harness is messed up somewhere.

Any thoughts?

Thanks!
 

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Is it normal to have 0.3 Ohms resistance between battery negative terminal and the rest of the grounds with ignition off AND 6.3 with ignition on?
Yes. When the key is On, current in the ground wire will produce a voltage. This voltage (and it may be tiny), is enough to corrupt the meter measurement.

The best way to measure a ground wire or ground connection is with a voltage-drop test, not a resistance test. To do a voltage-drop test, put the meter in voltage mode then connect the probes to opposite ends of the ground wire or ground connection in question. With power On, if the ground wire or ground connection is good, there should be almost no voltage drop.

What's the correct voltage of the O/R wire? I have 0.78 either with the original switch setup or with the 100 Ohms resistance grounded. The same exact value.
Raul, Can you measure the voltage on the O/R wire on your working SV650? That would make for an excellent comparison. I believe you should see about 4 to 5 volts.

Is it normal for the meter to show different values when switching the positive and negative probes between them? (6.3 Ohms with red pole at ground and black pole at battery negative terminal versus 0 Ohms with black pole at ground and red pole at battery negative terminal)
Yes. If the meter reads different resistance values when swapping the probes then there is voltage in the system, or there is some type of electronic device in the path.

If I have spark, that means the harness is messed up somewhere.
Any thoughts?
If you get really stuck, that would be a good test.

Hang in there, you will solve this. As you show in your wiring diagram, the ignition on the gen1 SV is pretty simple.
 

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Discussion Starter · #19 ·
Thanks for the clarification of the different resistance values between switch on and off.

Unfortunately, I don't have a running SV :)

I will probably do the simplified version of the harness and see what I get.
 

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Discussion Starter · #20 ·
I also thought to make a minimal required harness and to test out like this:

View attachment 63196

With an external battery, with the coil assembly taken out of the bike.

If I have spark, that means the harness is messed up somewhere.

Any thoughts?

Thanks!
Hello guys,

So with this configuration, I have a big, fat spark.

The million dollars question is now... What the hell should I do next? I feel like the hardest part became now the easiest (checking if all parts are OK).

Thanks alot!
 
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