2008 Ulysses no spark

[pdksh]

Folks, its been too long.

Obviously my fleet of buells has been running well, or you would see more posts. I'm about to start searching here and Bad Weather, but I thought I would take a shot.

2008 XB12XT
33,000 miles
Factory ECM/Tune
Factory Pipe
ECM relocated and visually ok

This weekend the bike cut dead, like someone hit the kill switch. The bike safely coasted to the side of the road, about 30 miles from home. The bike just dropped, no sputter, cough, chug. Bike has a quarter tank of gas. I pulled off the left air duct and did a basic spark check on the front cylinder. NO SPARK, holding the plug to the engine chassis ground. Immediately I suspected the Crank Position Sensor (CKP) or cracked ECM, and trailer'd her home. The clean spark plug feature worked so I didnt suspect the coil. Bike just cranks and cranks, not even attempting to catch. Obvious FUELL/IGNITION issue.

Of course no CEL Error or DTC codes in memory

Started with the basic tests using ECM Spy
- PASSED front coil test - visually confirmed spark
- PASSED rear coil test - visually confirmed spark
- fuel pump cycles and sounds like it always has
- tack reports 300 rpm while cranking
- CKP reports activity while cranking

Actions Taken
- Swapped with good 2008 ECM
- Swapped Coil, spark plugs and wires
- Swapped Bank Angle Sensor (BAS)
- metered ECM harness to CKP lines
- tested voltage on coil line 2
- removed BAS and then tested when shorted BLACK to GREEN wires
- reviewed ground connections under seat and triple clamp, installed star washers and metered
- metered ground pins on ECM wire harness
- Volt Meter across CKP lines shows 5v AC while cranking and CKP meters 990 ohms (looks good according to the electrics manual)
- pulled fuel line and primed the pump, about a quart of fuel ended up in my lap, thank fully no spark to set me on fire. I suspect the fuel pump is ok

OBSERVATIONS
- when bars are cranked to left hard stop, the spark plugs will spark (front and rear) until i stop cranking - This is very intermittent
- playing with the ECM wire harness at the ECM will sometimes get the spark plugs sparking - Again very intermittent
- this was at the end of the day, my battery was toast, even with a charger

At this point I have not 100% ruled out the CKP sensor, I'm leaning towards a bad/broken wire in the harness at either the triple clamp or the ECM

Suggestions??? Observation??? Humorous Story???

I will keep this thread updated, nothing worse than a thread that just ENDS! "did it get fixed?" "did you sell the bike?" "were you abducted by aliens?"

 

[pdksh]

I forgot to mention that I metered all fuses (good) and swapped the relays around. They appear to be the same part number (stamped in the plastic) still no love...

 

[cvc]

if it sparks with the bars cranked to one side then you already know where to look next ohm the ignition and kill switch wires, also if you get intermittent spark when playing with the ECM harness then you have a broken/bad wire .
" I'm leaning towards a bad/broken wire in the harness at either the triple clamp or the ECM "
let us know what you found good luck those issues are time consuming but not complicated and I print pictures of the connectors so I can make notes circle each end test then slash through the circle after you test each don't forget to wiggle the wires while testing. worst to be in a "good " spot and mark the cheat sheet good when it isn't.

 

[Cooter]

Yup CVC nailed it.
You have a multiple main ground at the steering neck as well.
Check voltage at the red run switches OUT wire all the way to the ECM, key on switch on. Swing the bars, move the harness etc. If you lose voltage just keep moving back on that circuit (connector under the wind screen, the switch itself, the key switch, the supply voltage at the fuse box)
Check that ground connection.

 

[pdksh]

the grounds are all good, At the neck and the two under the seat. Added fresh star washers and checked for broken connections. I will tear into the triple clamp and wire harness after I give the bike a "time out" Maybe this weekend. I do need to check the ignition switch and kill switch. So far the voltage on the red run switch checks ok, but it it was ok the bike would be working.

UGH...

 

[Cooter]

From the way you describe it, you lose spark when you wiggle the wires? That would def be on the primary side, either to the coils or from the key/kill switch. I have an Ohm meter that beeps with continuity so I can hook it up and wiggle wires without having to look at it. Lose the beep, lost continuity. Makes finding that annoying junk much faster If you don't have one like that, they're cheap.

 

[pdksh]

actually I get spark intermittently when I wiggle the wires. As a rule, no spark. Yep a nice/beeping FLUKE meter. Ill go over the kill switch/ignition switch. Need to get the current bike of the stand so I can start trearing this one apart :-(

 

[Cooter]

Meaning the coil would fire with the ignition on... not running?! The narrows it down to the 2 signal wires that go from the ECM to the coil. Each wire controls one cylinder and grounds to make spark. One on each end of the coil.

There is a "dyna loop" built in to one of those wires to suppress cross noise. It exits the harness and makes a loop right at the battery tray (yellow/red IIRC) since it is a naked wire right next to those sharp edges and on a paint shaker, you should check that.

 

[cvc]

harbor freight has a toner for tracing wires for about $30 might make finding the break easy the tool works but they dont seem to last but a fluke toner is several hundred

 

[Outlaw]

Power Probe makes a decent one also

 

[pdksh]

Found three wires in the triple clamp area that failed the “pull test” patched them, but still no love. Very intermittent spark, the clean spark plug feature and ECMspy test both fire nice. Still cranks and cranks. The CKP sensor reports 6vac and that wire to the ecm meters fine, so does the ecm to coil wires. Going to recheck the grounds under the seat.

On a high note, when I pulled the front forks for better access to the triple clamp, I found a really bad wheel bearing