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Discussion Starter · #1 ·
Hey all.

A few weeks ago I got my dream bike - an exceptionally clean 2000 XX with 2200 miles. It's been a dream to ride and has been running perfectly. I took it for a several hour ride last weekend and noticed no issues. Two days later I go to take another ride and the engine won't start. The fuel pump primes, all lights work, the engine turns, but does not start.

I noticed the FI light flashing 1 long and 9 short which my service manual says is the ignition pulse generator. I lifted the tank and was able to disconnect/reconnect the 2P connector, but no change. I suppose it really could be a faulty generator? I will do a continuity test later today.

I also inspected the infamous wiring loom test block and saw no sign of corrosion or water. This bike is seriously clean - it's been garage kept its entire life and doesn't have a single spot of rust, pitting, corrosion, anything. But just to be safe, I cut the test block off and spliced the appropriate wires together according to the forum posts, but no change. I think I did it right because with the cap off, turning the ignition on would not prime the fuel pump, but with it on/after I performed the fix it works normally again. Could that be a clue?

The only thing I can think of that happened is it sprinkled (very, very light rain for ~10 minutes) the day in between, which has me thinking a grounding issue, but I still can't believe how easily the bike would run perfectly and then entirely not start. That said, I'm handy with mechanical troubleshooting (I have rebuilt a few engines) but am quickly coming to the end of my electrical systems knowledge. I've been rereading the FI section of the service manual but am getting a bit overwhelmed with many new concepts and troubleshooting techniques that I don't quite understand.

So already completed:
  • Charged the battery up
  • Disconnected/reconnected the ignition pulse generator connector
  • Hardwired/replaced the loom test block
  • Disconnected/cleaned/reconnected all the connectors I could find under the seat, including the ECU

My current plan is:
  • Continuity test on the pulse generator
  • Look around for things that look like grounds and clean them (I'm not entirely sure what I'm looking for though, page numbers in the manual would be helpful)

Does this make sense to everyone else? Could a pulse generator really go bad with so few miles? Should I be checking anything else? Talk slow and use small words, I am not very experienced with electrical :) Thanks in advance.
 

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With such low miles she almost belongs in a museum. Not many left with sub 2500 miles.
Anyway, using the credo "use it or lose it", super low mileage can bring its own problems. I recommend going over all consumable items such as hoses, tubing etc. Also the FPR (fuel pressure regulator) which can develop a pinhole leak and pull fuel into the engine via the vac hose. Not forgetting the brake/clutch fluid/hoses.

Regarding Ignition pulse generator, to check, the manual says;

1. Pull connector and check each wire for continuity with ground. Should be none.
2. Same connector, check for peak voltage while cranking. Should see 0.7V min.

Or, pull a plug wire and connect to spare spark plug, rest on block and crank to check for spark.
 

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Don't overlook the simple stuff, like the RUN/kill switch, especially in an older bike that's recently been exposed to some weather. Moisture/corrosion can be an issue within the switch.
 

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Test that battery with a multimeter.........

Best way is to leave the charger unplugged overnight, then on 1st start in the morning look for >9.5v preferably 11v while cranking, if the battery is under 9v it likely does not have enough amps to run the injectors and coils while cranking the engine.

The loom fix' does not apply to FI Birds, especially those that have not been ridden in rain for many years.

If it isn't as simple as a battery failure, it could be the reason it has almost no miles on the clock and might be why it was sold........

Good luck, but the FI Birds should be super reliable - I've owned 2 of them, still have my 05, and it still leaps into life on demand......but I don't use tired batteries getting by because battery charging makes them look ok.

Good luck, that barn find should run like a tight new bike........

(y)
 

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Don't overlook the simple stuff, like the RUN/kill switch, especially in an older bike that's recently been exposed to some weather. Moisture/corrosion can be an issue within the switch.
Other very simple overlooks…

- kill switch still engaged (as opposed to the set at Run but dirty contacts scenario),

- starter switch… likewise prone to dirty contacts.

- bike left in gear: so won't start until you
  • put it in neutral, or
  • engage clutch (assuming clutch safety switch working okay), and
  • side stand isn't down (and side stand safety switch working okay
I know it all sounds daft, but we've all done or experienced one or all the above over the years!

Other query sometimes overlooked is does the bike have an alarm/ immobiliser. I had a fault in my Datatool S4 wiring resulting in the alarm immobilizing my bike (all electric lit up but bike wouldn't start until I found the loose wire).

Rgds Mallow1
 

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If she turns over, you could try some starter fluid easy start spray to see if it catches to fire, I think if you can split it in to, electrical or fuel it mite help figure out what is going on.
You can do a fuel flow test, get your self a manual, I think theres one on the site, and it should tell you how to check for fuel flow.
And the other easy one is check for spark on the plugs and take it from there.
 

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Discussion Starter · #8 ·
Hey all, thanks for your responses - didn't get a chance to take a serious look again until now.

Bad news: My multimeter was bad
Good news: The new multimeter found no continuity on the ignition pulse generator connector (as the service manual expects)
Bad news: There's no voltage coming from the other end - the ignition pulse generator wire that leads around to the right side and into the engine cover
Good news: After fiddling with the wire, it started right up again
Bad news: After lowering the tank back down, it will no longer start again

If I fiddle with the mass of wires where the connector is under the tank on the left side, it randomly will start. Jiggling the wires while it's running does not cause it to die. The connector looks totally clean, but I have cleaned it several times, so I don't think it's invisible corrosion. The mass of wires under the boot pictured here in a dotted line circle:
Motor vehicle Automotive design Painting Rectangle Naval architecture


The connector itself looks fine. The terminals coming from the generator move slightly within the connector but so do all the other ones. It does seem to be narrowed down to that area because it randomly does or does not start after fiddling with those wires when all else is equal (on the center stand, tank raised, in neutral). I will keep trying to isolate the variables and find a pattern... but do you all think it might be worth just replacing the pulse generator, a $50 part brand new? I would have honestly preferred it to be definitely dead... then I could stop wondering. I don't want to be wasteful though.

With such low miles she almost belongs in a museum. Not many left with sub 2500 miles.
Anyway, using the credo "use it or lose it", super low mileage can bring its own problems. I recommend going over all consumable items such as hoses, tubing etc. Also the FPR (fuel pressure regulator) which can develop a pinhole leak and pull fuel into the engine via the vac hose. Not forgetting the brake/clutch fluid/hoses.

Regarding Ignition pulse generator, to check, the manual says;

1. Pull connector and check each wire for continuity with ground. Should be none.
2. Same connector, check for peak voltage while cranking. Should see 0.7V min.

Or, pull a plug wire and connect to spare spark plug, rest on block and crank to check for spark.
Definitely good advice. I'd already checked out all but the FPR before starting to ride it, and the rubber is all in great condition. The only thing is the brake fluid is slightly discolored which I will be replacing soon. That test is what I had in mind from my service manual.

Was your battery dead the first time she wouldn't start?
When you did the loom fix, was there any corrosion in the plug or wires?
No, the voltage on the battery was fine, but I did it just in case.
No visible corrosion whatsoever on the plug or wires.


Don't overlook the simple stuff, like the RUN/kill switch, especially in an older bike that's recently been exposed to some weather. Moisture/corrosion can be an issue within the switch.
The starter motor runs 100% consistently when switched to run. Would a faulty switch manifest that way?

Test that battery with a multimeter.........

Best way is to leave the charger unplugged overnight, then on 1st start in the morning look for >9.5v preferably 11v while cranking, if the battery is under 9v it likely does not have enough amps to run the injectors and coils while cranking the engine.

The loom fix' does not apply to FI Birds, especially those that have not been ridden in rain for many years.

If it isn't as simple as a battery failure, it could be the reason it has almost no miles on the clock and might be why it was sold........

Good luck, but the FI Birds should be super reliable - I've owned 2 of them, still have my 05, and it still leaps into life on demand......but I don't use tired batteries getting by because battery charging makes them look ok.

Good luck, that barn find should run like a tight new bike........

(y)
The battery is around 11.5v while cranking.
From the forum posts about it, I understood the loom issue was most prevalent among 99-00 models and could manifest as quickly as a year, so they "fixed" it in the 01+ models by moving the plug further up the harness so moisture wouldn't collect there. Is that wrong? This is a US model if that matters.

Other very simple overlooks…

- kill switch still engaged (as opposed to the set at Run but dirty contacts scenario),

- starter switch… likewise prone to dirty contacts.

- bike left in gear: so won't start until you
  • put it in neutral, or
  • engage clutch (assuming clutch safety switch working okay), and
  • side stand isn't down (and side stand safety switch working okay
I know it all sounds daft, but we've all done or experienced one or all the above over the years!

Other query sometimes overlooked is does the bike have an alarm/ immobiliser. I had a fault in my Datatool S4 wiring resulting in the alarm immobilizing my bike (all electric lit up but bike wouldn't start until I found the loose wire).

Rgds Mallow1
I thought it might have an alarm as well since the keychain had a Gorilla fob, but there's nothing attached to the battery and nothing spliced in anywhere as far as I can tell.
 

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Hmmm, see if you can get her started again with the tank raised, and try and repeat what you did.
You could try a bit of easy start spray when she dies, so if it bursts into life after a spray, it mitd be a fuel thing.

The classic fuel air spark mite be in order.
If you have the right side lower fairing off, when you lower the tank get a torch and shine it under your tank, see if the fuel line is ok and the return line.
Is weird though by lowering your tank and stopped running.
 
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