No spark, 2002 Bandit 600

Bought a used one with 31k miles on it.  Japanese motorcycle electronics are pretty bulletproof, especially with just 31k miles.  Not this time though.


- coils are getting battery voltage when the ignition switch is on (of course, the other ends of the coils are wired up to the ECU ignitor, which decides when to cause the spark)
- the ECU is getting battery voltage correctly when the key is on
- I shorted the wires for the sidestand switch to remove that as a possible reason for no spark
- the neutral light works on the dash
- put in new spark plugs to eliminate the old plugs as a possible cause
- verified that both the 1,4 coil and the 2,3 coil are getting battery voltage on one side but neither the (1,4) or (2,3) plugs fire, meaning whatever the problem is, it is affecting *both* coils
- the oil light comes on on the dashboard
- checked the Pulse Generator Coil resistance -- it's 175 ohms, well within the 135 to 200 ohms specified in the Haynes manual

EDIT:  Forgot that earlier in the day I checked these too:
- verified the the 'Off/Run' handlebar switch works correctly
- verified the fuses are all okay including the ignition fuse


I need to know what else can I check -- have I missed anything?  Trying to determine with certainty what the exact fail point is in the electrical system on the bike, as opposed to buying new components and pray they work

Clutch switch?

Bosco15 wrote:Clutch switch?

Forgot to mention, I didn't test it with my multimeter, but it's working in the realm of not allowing the starter motor to crank until I pull the clutch lever in.   Could that behavior basically eliminate the clutch switch as a reason for no ignition?  If not, I'll need to find the connector where it gets to the harness and test it with my meter tomorrow.

I guess a reasonable question here is this.   With the ignition switch on, I see battery voltage on both coils on one end.

As I crank the starter, my assumption is the ECU, which connects to the *other* end of the two coils, must be doing something electrically those other ends of the two coils -- what would that be?  If I check for voltage on the other end of each coil, will I see that the ECU is dropping that other side of the coil to ground?  Or isolating (open circuit-ing) the other ends of the 2 coils *from* ground?

I should be able to see if the ECU is correctly shunting or opening the ends of the two coils that are opposite from where I read battery voltage today, but I'm not sure what I should see on those opposite coil ends -- ?

http://www.dansmc.com/cdiignition.htm

This may help. It may not. 

Thanks -- it's a good read there; still hoping it's not my ECU

Just to confirm.............did you remove each/any of the plugs to witness visible presence/absence of spark while cranking?

WISA wrote:Just to confirm.............did you remove each/any of the plugs to witness visible presence/absence of spark while cranking?

Yes, and none of them have spark.  I installed 4 new plugs too, and no spark.

ok, well I'm no expert on the 2002 600 bandit,.............but,  the firing of coils by ignitor modules is similar in most applications.........the coil is energised by 12v from the battery thru the coil to earth/ground thru the ignitor module. The pulse generator triggers the ignitor to collapse/open the coil circuit, which it (the ignitor/ecu module) does by interrupting the earth path the coil is using, which causes the coil to discharge its energy to the spark plugs.

Perhaps you could use a test light to verify the coil circuit is actually being interrupted/triggered by the ignitor/pulse generator side of the circuit!............... With a test light connected across the coil, (clip to one coil terminal and probe to the other) the light will illuminate when the coil is charging and go off when the ignitor/ecu interrupts the earth....short starter cranking pulses should display on/off cycles.......
Given that you aren't getting any spark you might expect  not to get on/off cycle but one or the other , but at least you can confirm that and know/work from there......

WISA wrote:ok, well I'm no expert on the 2002 600 bandit,.............but,  the firing of coils by ignitor modules is similar in most applications.........the coil is energised by 12v from the battery thru the coil to earth/ground thru the ignitor module. The pulse generator triggers the ignitor to collapse/open the coil circuit, which it (the ignitor/ecu module) does by interrupting the earth path the coil is using, which causes the coil to discharge its energy to the spark plugs.

Perhaps you could use a test light to verify the coil circuit is actually being interrupted/triggered by the ignitor/pulse generator side of the circuit!............... With a test light connected across the coil, (clip to one coil terminal and probe to the other) the light will illuminate when the coil is charging and go off when the ignitor/ecu interrupts the earth....short starter cranking pulses should display on/off cycles.......
Given that you aren't getting any spark you might expect  not to get on/off cycle but one or the other , but at least you can confirm that and know/work from there......

That's what I was trying to remember -- the behavior of the coil.   I previously verified that one side of both coils was getting battery voltage when the ignition was turned on, so I knew that that half of the behavior was fine.

What I couldn't remember is how the *other* side of the coil works, and thankfully you've made it really easy to understand. 

So in addition to pegging a test light across the coil then slowly cranking the engine -- which will give excellent visual confirmation if the pulse generator and ECU are working right --

here are a couple other things I'll check, using my multimeter, before I go out to Harbor Freight Tools and try to find a test light:

1)  ignition on, 12vdc on one end of the coil (previously verified) -- before cranking, is the other side of the coil (the "ECU/pulse generator side of the coil") at ground (earth), ie. if I measure resistance from the bike's ground to the ECU side of the coil, is it properly grounded?

2) now crank the engine in small increments, continue to measure resistance from the bike's ground to the ECU side of the coil -- does the ECU side of the coil show a change, alternating between ground/infinite resistance, as the engine turns over?


Thanks for explaining how the ECU and pulse generator act on that opposite end of the coil,  this will help to narrow down the fault.  If I find that the coil's  ECU side is *not* alternating between ground/infinite resistance/ground/infinite resistance,  seems like that would indicate

- the pulse generator is not pulsing, OR
- the ECU *is* getting proper pulses from the pulse generator, but not passing that on to the coil, OR
- the ECU does not have a proper ground itself, in which case that side of the coil will always read infinite resistance to ground

The explanation of the ECU side of the coil really helped here, thanks, let me check this.

Got some free time to try the suggestions.


1)  I took the battery out of my daily driver 1998 Bandit 600.  I took it for a long ride to make sure the battery was charged up -- measured just around 13vdc before I transferred it to my 2002 bike.
- no change.  Still no spark.


2)  I measured my 1998 battery while cranking my 2002 bike -- it dropped to 10, 9 volts while cranking the motor, then right back to 12-13vdc when I let off the cranking.  

(NOTE:  After all my troubleshooting today, when I put the battery back into my daily driver 1998 Bandit 600, she started right up without hesitation.)

3)   I turned on the ignition and for each coil, I read the volts at each side of the coil during cranking -- THEY WERE ALWAYS THE SAME!  9 or 10vdc.   That right there explains (maybe?) why the coils never generate a spark -- during operation, to collapse the field of the coil (which generates spark), one side of the coil *must* change to be different from the other side or the field will never collapse.  

Since most coil-based ignitions work the same -- meaning:

A)  one side of the coils gets battery voltage when the ignition is turned on -- on the 2002 Bandit 600, the orange/white wires supply battery voltage to one side "A" of the two coils

B)  the other side "B" is provided a ground (and in the 2002 Bandit's case this other side gets its ground from the ECU, either the white or the black/yellow wire depending on which coil),  so *normally* there is current flowing in the coil, and a spark is generated when current stops flowing

C) as the crankshaft rotates, the pulse generator signals the ECU to remove the ground from side "B" of the coil

D)  and then current stops flowing in the coil, the field collapses and that generates a spark


So I checked for *any* change in voltage on the "B" side of the coils -- I wanted to see if the ECU did its job, cutting off the ground -- NOTHING.


Now it's entirely possible that the pulse from the pulse generator/ECU is so fast that my $6 Harbor Freight multimeter's gauge cannot respond quickly enough.


I checked the "B" side of the coils for resistance to ground -- OPEN CIRCUIT, all the time, even while cranking the motor.

I've used oscilloscopes plenty of times, and the very short time duration of the pulse may only be read-able on an O-scope.

So to sum up, I read battery voltage on *both sides* of the coil ALL THE TIME.  It never changes.   Unless I need an oscilloscope to catch the changes, having both sides of the coil read battery voltage *all the time* is why no spark is generated.   That "B" side of the coils *must* change relative to the other side of the coils or no spark will happen.

There's a lot of things that can cause that on the 2002 Bandit:
- bad start/stop handlebar switch;
- bad "kickstand down" switch;
- bad "kickstand down" relay (which is in the end tail of the 2002 bike next to the fuse box).
- bad ignition switch;
- ignition fuse blown;
- bad pulse generator (right end of the crankshaft);
- bad wiring somewhere (for example, is the ECU being supplied a ground?)
- bad ECU

I verified that the ECU is getting a proper ground fed to it, through its black/white wire.

I have eliminated all but the pulse generator and ECU.  And according to the Haynes manual, the pulse generator coil is supposed to ohm out at  between 135 to 200 ohms; my bike shows 170 ohms.  So the pulse generator *coil* part seems okay.  The other half of the pulse generator is a spinning plate that is bolted on the (right side) end of the crankshaft.  As this plate spins, it interacts with the coil to produce a spark at the right time.


I DID LEARN SOMETHING NEW.  I always wondered why, when I got the bike, the right side of the engine at the crankshaft has a different colored cover (black) than the rest of the engine (goldish).

When I pulled that black crank cover off, the bottommost screw of the pulse generator was ground down from a right-side down at some speed.  The screw is so badly ground down, I cannot fit a phillips screwdriver in the head -- I'll have to use a pair of vise grips to get hold of the head of that screw to remove it.

That right-side down at some point in the bike's history got me thinking -- MAGNETS LOSE THEIR MAGNETISM sometimes if they suffer a hard physical shock.

Is the part of the pulse generator that has 4 "wings" and is attached to the right end of the crank magnetized?

Because in that case, even if the pulse generator coil reads between 135 to 200 ohms -- if the spinning part of the pulse generator has lost magnetism that it might originally have had, that would explain why NO PULSES happening.


Anyone know if the spinning part of the pulse gen is normally magnetized?  The spinning part I'm talking about looks like the item on the left in this picture -- this isn't a Bandit pulse gen, it's from a 2007 GS-500, but the 2002 Bandit has one looking like this:




Seems like, since the thing on the right in the photo is a coil, that spinning part *must* be magnetized or it would have no effect on the coil part on the right.

Anyone have an idea about this magnetized bit?


HERE'S THE 2002 BANDIT 600 WIRING DIAGRAM I'M USING (from the Haynes manual):

G'day greatDays,

Have you ever witnessed the engine running?

Everything seems to point back to the ECU (or Pulse Generator)....

It is not always successful using a DMM to check fast changing values like ignition coil on/off voltages while cranking/running......the refresh rates are usually far too slow and they normally appear like the voltage is barely changing.
  
Another alternative might be to remove the cover and align the rotor in the firing position, with ignition on....that's where the ECU/coil(s) should be grounding. Maybe rotate the engine slowly by hand thru a revolution or two with ignition on and set to run, checking for on/off voltage at the ign. coils. (For ease and safety take the plugs out first)...even safer to turn off ign. while rotating to position and switch on to check meter.

I don't think the rotor is magnetised on these.....The pulse generator/pick-up coil probably has a magnet in it ....the rotor is usually just a ferrous disc/lobe......the passing lobe changes the electro magnetic values/flux/inductance etc  ergo, the pick-up coil's signal voltage, and that changing voltage is the ECU's trigger.

.......cheers

WISA wrote:G'day greatDays,

Have you ever witnessed the engine running?

Everything seems to point back to the ECU (or Pulse Generator)....

It is not always successful using a DMM to check fast changing values like ignition coil on/off voltages while cranking/running......the refresh rates are usually far too slow and they normally appear like the voltage is barely changing.
  
Another alternative might be to remove the cover and align the rotor in the firing position, with ignition on....that's where the ECU/coil(s) should be grounding. Maybe rotate the engine slowly by hand thru a revolution or two with ignition on and set to run, checking for on/off voltage at the ign. coils. (For ease and safety take the plugs out first)...even safer to turn off ign. while rotating to position and switch on to check meter.

I don't think the rotor is magnetised on these.....The pulse generator/pick-up coil probably has a magnet in it ....the rotor is usually just a ferrous disc/lobe......the passing lobe changes the electro magnetic values/flux/inductance etc  ergo, the pick-up coil's signal voltage, and that changing voltage is the ECU's trigger.

.......cheers

Thanks, really helps,  I'm going to try it.  That is a brilliant suggestion to rotate it slowly by hand and line the pulse gen's rotor with the pickup coil.
 
One of the things I got with the bike was a spare ECU so I'll try that too.  He told me at time of sale that he wasn't getting any spark.   I was a bit overconfident in my ability to fix it quickly.  I did get a great deal (said the man with a 500 pound possible parts donor bike).  Dang it.

Having got a spare ECU says the original owner suspected something serious with the ignition. You might have two dead ECU's.

On your circuit diagram you state you found a short across two wires of an "orphaned connector", this would be putting an earth directly to the ignition fuse and would be blowing it, hopefully it has not done any other damage to wiring, side stand relay or the ECU.

Can you see the pulse generator plate spinning as the motor is cranked ?

Your theory on how the coil works is pretty spot on.  Have you tried putting +12v to one side of the coil and tapping the other to earth to get a spark, that will tell you whether they are okay.  If you're game (and in good health), hold onto the coil wire whilst cranking the motor, there's very little current but you should definitely feel a kick if the ECU is doing it's job, my guess is that there will be nothing.

Having tried almost everything, you are getting down to limited options, try to get a running bike and start swapping parts over (and hopefully not blow up the good bike , or pay a bike garage to hook it up to their scope and gauges to isolate the problem, they should be able to do that within an hour.

Good luck.

Having got a spare ECU says the original owner suspected something serious with the ignition.  You might have two dead ECU's.

On your circuit diagram you state you found a short across two wires of an "orphaned connector", this would be putting an earth directly to the ignition fuse and would be blowing it, hopefully it has not done any other damage to wiring, side stand relay or the ECU.

Can you see the pulse generator plate spinning as the motor is cranked ?

Your theory on how the coil works is pretty spot on.  Have you tried putting +12v to one side of the coil and tapping the other to earth to get a spark, that will tell you whether they are okay.  If you're game (and in good health), hold onto the coil wire whilst cranking the motor, there's very little current but you should definitely feel a kick if the ECU is doing it's job, my guess is that there will be nothing.

Having tried almost everything, you are getting down to limited options, try to get a running bike and start swapping parts over (and hopefully not blow up the good bike , or pay a bike garage to hook it up to their scope and gauges to isolate the problem, they should be able to do that within an hour.

Good luck.

You're probably right about the 2nd ECU,  it came in a box of stuff with the bike and at that time, I didn't even know what an 'ECU' was, so didn't ask him about it.  Bought this bike some 5 years ago, and only now bringing it back to life.

Yes, the odd-shaped plate, which I'll call the PGR  ("Pulse Generator Rotor")  is spinning fine.

Here's something I will try, WISA suggested it.  If my multimeter cannot respond fast enough to register and correctly report the pulse coming from the Pulse Generator, and seeing as I don't own an oscilloscope, today I bought two different little lamps -- one is a single red LED, the tiny ones.     And I bought a larger bulb socket and some bulbs.  (I'm not sure if there's enough power for the bigger bulb, which is the size of a small taillight bulb, so I got the small LED just in case.)

I'll hook a bulb up to the
- Pulse gen
- ECU
- and the coils themselves

It the light flickers/changes, then I must have a good ECU, pulse gen, or coil.  Surely if I check each one of those, one at a time, I can nail the one causing the problem.  My guess is, because the prior owner had this bike down on its right side, bad enough to need to replace the right side engine cover that covers the pulse generator -- my guess is the pulse generator itself is the culprit.

   A digital multimeter may not be able to register and display a short-duration pulse -- but a small light simply *must* come on (or go off) briefly at the time of the pulse, and that flicker of the bulb will tell me if I'm not getting output from the ECU, or the Pulse generator, or the coil.   My thinking is, unlike a digital multimeter, a simple light will respond quickly enough to a brief pulse, ie. brief change in voltage, with a quick flicker in the amount of light it's giving off, to be detected by the human eye.

The small lamps I bought costs around $5, how can I lose.  Will check tomorrow.

If your test lights don't do the job, try and source a analogue multimeter, with a needle not a LCD display. Analogue meters a generally more sensitive to voltage changes and may show a pulse in the needle sweep

The "PGR" is bolted to a shaft that is connected to the crank and spins in time thus giving the ECU the pulses to fire the coils.

If you unbolt the PGR from the shaft (hopefully it is keyed so can easily go back in the right position), you should be able to manually wave one of the 4 rotor ends near the magnetic pickup to trigger the ECU, might be a little easier to trace the fault than turning the motor over all the time.

madmax wrote:If your test lights don't do the job, try and source a analogue multimeter, with a needle not a LCD display. Analogue meters a generally more sensitive to voltage changes and may show a pulse in the needle sweep

Sheesh I have one of those,  I hadn't considered that.  Thanks for that suggestion.
It's an old one I got from Radio Shack maybe 20 years ago.   I'm gonna try that first, it has a 3" long needle that will be much easier to see than trying to catch a microsecond of a glow from a small bulb.  The needle can't be missed.

This is what I have:



It's all cheap plastic on the outside but the reliability for the past 20 years has been excellent.  Again thanks for the reminder.

Definitely worth a try.

Hey Greatdays. 
Did you find the problem with your bike? Solve it?
I have just lost spark on the 1200 & am just starting to go through the process of elimination.  
Found a couple of corroded pins in connectors so far, but no spark. 
Aaarrrgggg!!!

Bosco15 wrote:
Aaarrrgggg!!!

Damn! Did I miss International Talk Like a Pirate Day, again!

Re-Cycled wrote:

Bosco15 wrote:
Aaarrrgggg!!!

Damn! Did I miss International Talk Like a Pirate Day, again!

Eyeee!

I take it that GreatDays has not got his bike running as yet.

Here is a fascinating article from the VSRI forum regarding an anti-theft device built in to I assume several Suzuki motorcycles.

It is an undocumented feature involving the ignition switch and ECU

http://www.vstrom.info/Smf/index.php/topic,6186.0.html

In summary, it involves an incompatibility between ignition switches on several models maybe back as far as 1997 which prevents the bike from starting.

Anyway, I thought it was too good not to share especially with others who like to tinker and swap bits.

I don't want to send GreatDays off on a "wild goose chase" but it is just another item to consider.

BanditDave wrote:I take it that GreatDays has not got his bike running as yet.

Here is a fascinating article from the VSRI forum regarding an anti-theft device built in to I assume several Suzuki motorcycles.

It is an undocumented feature involving the ignition switch and ECU

http://www.vstrom.info/Smf/index.php/topic,6186.0.html

In summary, it involves an incompatibility between ignition switches on several models maybe back as far as 1997 which prevents the bike from starting.

Anyway, I thought it was too good not to share especially with others who like to tinker and swap bits.

I don't want to send GreatDays off on a "wild goose chase" but it is just another item to consider.

Cheers Dave. 
The more clues or avenues to explore, the better.  
My Bandit hasn't missed a beat, since I bought it from Rolls. 
One morning she has no spark. Cranks ok. Fuel ok. Air ok. No spark. No go.
I'm sure that it will turn out to be a corroded something not giving a correct earth or signal. But finding it is the challenge.