| Author | Message | ||
     Olbolt |
Can an stock ECM partly fail? '99S3 here's a new and repeatable event; with ignition on, and Engine Run switch on, in Neutral, Clutch disengaged, Check Engine Light won't illuminate, and Fuel Pump won't cycle unless the side stand is retracted. The engine won't crank or start with the sidestand down! After engine running (with side stand up) and I extend the side stand, the engine shuts off exactly as if the Engine Run Switch was turned off. Check engine light is off also. Other starter interlock functions remain; Won't start in gear unless clutch is disengaged, will start in Neutral with clutch in or out. No faults show with a blinking Check Engine Light. No faults show thru the ECM Spy, however sometimes the Tach and TPS don't indicate on the ECM Spy screen. when this happened, I did run the tach diagnosis, and it passed, with the Buell tach showing ~ 3k rpm for the test period. I'm thinking something changed inside the ECM, as I used to be able to start with sidestand down. I need it to be reliable as an extended trip is planned. Is this an opportunity for a new (race) ecm? Recent additions include Buell heated grips, and hand guards, and top end gaskets. Thanks in advance for your comments.. | ||
| Pkforbes87 |
My neutral switch went bad and caused similar problems. The tranny could physically be in neutral, but the switch didn't know that and would kill the engine any time the kickstand was down without the clutch lever being pulled. Do S3's have a neutral indicator light on the dash? If so, is it illuminating like it should when the tranny is in neutral? | ||
| Olbolt |
The S3 has a neutral indicator light, and it works like it should, with the ignition on, illuminated in neutral...extinguished when in gear, no matter what position the side stand is in. Thanks for the suggestion though. | ||
| Oldog |
Olbolt bypass the stand switch and see if the problems continue, the ECM outputs can fail generaly the attached item quits working, altogehter wiring issues are far more common and these are intermitting problems bad connector '/ switch etc. | ||
| Olbolt |
Oldog, 1)I bypassed / jumpered the stand switch and as expected, it started. 2)Then I tried to start with jumper removed, and surprisingly it started! 3) At some point in today's adventure, the check engine light started flashing ~10 rapid flashes, a pause, then ~ 10 rapid flashes...ongoing. 4)Next I reconnected the side switch, now it starts with the stand either up or down, but the ~10 rapid flashes continue. 4)The ECM Spy was connected, but failed to indicate Tach speed on the Overview, and was unresponsive on the Throttle Position, sometimes indicating ~7.1, sometimes no reading, in both situations, not picking up throttle movements. No faults indicated. ECM Spy issues are as a sidenote, and it has preformed erratically as described well before my sidestand issues appeared. Part of the time it does work as it should. 5)I reconnected the stand switch, now it starts either up or down, still with ~ 10 rapid flashes on the Check Engine light. Comments appreciated... Olbolt | ||
| Pkforbes87 |
sounds to me like a wiring issue. Personally I would go through the wiring harness and inspect every connection as well as look for any frayed/exposed wires. reconnect all male/female connectors after cleaning the contacts and applying some dielectric grease. The grease is designed for high current applications like spark plug wires and coils, but it does a great job of keeping any moisture or corrosion out of your electrical connections. Just my $.02 | ||
| Oldog |
Sounds like the data port is shorting checking the wiring is indicated. | ||
| Olbolt |
Pkforbes, For contact cleaning, is it being suggested to unplug the connector & spray a cleaner on the metal parts, or mechanically assisting cleaning by scraping, then spraying & lubing? Any favorite products / tools suggested? I have seen a white discoloration on some non-contact areas, over the cad/zinc? plating, however I am reluctant start scraping away randomly, probably not really addressing the hidden functional areas. I like the suggestion of dielectric grease on the connectors, I am sure the connectors were originally assembled dry. Oldog, My Buelling is kinda like life.. first you don't know what you don't know, but with experiences & observation...( and the Buell Motorcycle Forum) you learn..(what you don't know) I'm going to go after the Data Port today. | ||
| Pkforbes87 |
I've never used a liquid or spray when cleaning connections. I just wipe everything clean with a dry shop rag and use a small flat screwdriver or scribe to scratch the surface of the individual contacts and verify that they are free of corrosion. Then apply the dielectric grease. This is all just what I do personally so it's very possible that a more effective method is out there. | ||
| Olbolt |
Good News!! Issues resolved with disconnecting / cleaning / dielectric greasing each wiring harness connector... Also did continuity checks on most including Starter/Ignition Interlock System wires fig. 7-11. All safety interlock functions now work as they should...including stand switch. Check engine light now functions normally. However no changes to ECM Spy occasionally working, but that may be the subject of a future posting, I have a few things to check-out yet. Interestingly, most of the harness connectors were tough to disconnect, and most had a small amt. of white powder on connectors. I did find 1 strand of copper wire on the relay block, touching a diode. This bike is a '99, and I have owned it one yr.+. It was extremely low mileage, and I don't believe it was ever wet..until I got it. So the connector powdering may have happened this past year. Clearly there was no evidence of dielectric (or any) grease on the connectors...bone dry! Thanks Pkforbes87 and Oldog, for your suggestions, and sharing your experiences. It meant a lot to me, and the issue was resolved quickly. So the answer to the original question...'Can a stock ECM partly fail?' for sure not in this case....It was the connectors, and it was readily correctable. | ||
| Oldog |
Ol'Bolt Good T'shooting The ecm and crucial connectors are Duetz ( the good stuff ) Dilectric Grease is always good to add to connectors in this environment. I wonder if the issues related to your comm problem with ECM spy are related to the wiring or computer settings? My bike started generating Error 15 IAT shorted to supply. I will grease the connectors now, and look for a short in the wiring run it reads the code with the sensor unplugged. When we share we learn.. |
