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Darth_villar
Posted on Monday, October 17, 2011 - 05:00 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Long story short, I tried just about everything other than hard wiring a relay for the fan to fix the skip spark.

Well I finally wired the relay, and am looking for a way to get the CEL off. I have already reprogrammed the ECM to run at different temps, so now I will just set it to run only at skip spark temps (which will throw the CEL, as I would like it to). There is an ECM value of Fan Feedback Loop, not quite sure what value that is.

I'm also not sure what throws the CEL for the fan being "unhooked". If it just needs a signal to pass through, I should be able to hard wire the pos and neg fan wires together. But I thought it may have to require some type of resistance to confirm everything is ok...

I won't have time to work on it again until next weekend, but if anyone has any other ideas or advice I'm all ears.

Phil
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Od_cleaver
Posted on Monday, October 17, 2011 - 07:37 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Don't wire the fan wires together.

From an old discussion on this forum, I think that the ECM monitors the voltage across the fan and not the current thru the fan. If this is the case a quarter watt resistor greater than 1K ohm should work. At least it will do no harm.
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Etennuly
Posted on Monday, October 17, 2011 - 10:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I did not worry about the CEL being on with my fan being hard wired to a switch. I look at it as a reminder to check on it once in a while.

It does take a lot of riding to get used to the light being on without having a worry about something else being wrong, but it has been running so damn good for the past two years compared to the perpetual run skip everytime the temps got to 70F, of before.

The real worry light is the one with the little V twin cylinders on it. That comes on......then you have a reason to hit the kill switch and coast to a stop!
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Towpro
Posted on Tuesday, October 18, 2011 - 08:43 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

What have you done to try to fix the spark skip problem?
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Rwven
Posted on Tuesday, October 18, 2011 - 09:02 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Riding in Texas 3 weeks ago. My wife and I rode to Galveston for a day. Temps 95-100. When I got back to my son's house I pulled into his garage and shut the bike off; the fuel began to boil in the frame/tank. I never went into spark skip mode once, There is something wrong with a sensor or it's related circuitry/program on your bike(s).
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Bike_pilot
Posted on Tuesday, October 18, 2011 - 09:04 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Maybe use the ECM to turn the fan on. The E B R programming is such that the fan is on whenever the bike is moving as best I can tell and I'm told that in tunerpro you can set the fan logic to be whatever you want.
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Etennuly
Posted on Tuesday, October 18, 2011 - 09:40 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

My '06 isn't all that smart, it's ECM would not turn the fan on when it needed to be on. I fought run/skip for over two years. My 'cure', although not hi-tech, was to simply run the ground wire to a manual switch on the bars. I have the CEL lit and don't care about that as long as the run/skip is gone.

I fire up the bike, let it warm up for about five minutes or so, then turn the fan on. I leave it on throughout the entire ride. Never have seen spark/skip since.

When the temps are below about 55F I do not turn the fan on at all.

I replaced the ECM with a known good one, it still did run/skip, I tried another, the same. I did all kinds of wiring repairs(each with it's own symptoms), retarding the timing, comfort kit, different oils, and many other things that sometimes temporarily 'fixed' it. The problem always came back. My override switch is the only thing that has worked.

Something evil lurks in my bikes ECM controlled fan cooling system. It has to be. There were several times it would be 'fixed' for hundreds of miles, and it would 'learn' the repair, then alter itself to make run/skip happen again! Cutting the ground to the ECM killed the evil one, and allowed me to have control of the cooling fan.
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Rwven
Posted on Tuesday, October 18, 2011 - 10:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Have you had the temp sensor on the bike evaluated or replaced?
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Darth_villar
Posted on Tuesday, October 18, 2011 - 10:12 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Thermo tec heat barrier on the inside of the frame, ceramic coated exhaust, changed timing, custom larger oil cooler.

Riding in Phoenix I would get skip spark cruising over 85 mph when it is 90+ degrees outside. I ride pretty much every day, so it has been annoying, now I just need the time to test the fix : )

Edit: Also used a different ECM, and replaced the head temp sensor. Keep in mind I'm running a big bore kit, so that may very well have something to do with it.

(Message edited by darth_villar on October 18, 2011)
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Etennuly
Posted on Tuesday, October 18, 2011 - 11:22 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If anything, from what I have seen, your big bore kit may be helping. Those of us who have been working through this a couple of years ago had it happen a 70F degrees at 70mph or less, we could not make it to 80 mph or even over 65 on a ninety degree day.

My ETS was also replaced and tested several times.
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Portero72
Posted on Tuesday, October 18, 2011 - 11:33 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I had the same issue(among many others), many moons ago, which ultimately led to the dealer buying back the bike. the S/S condition did NOT rear its head until immediately AFTER the original fan had been replaced. After which, S/S would show up on 70 deg days, running 50 mph, conditions it should not have. My uneducated guess was some small difference in the new fan. Like others, my dealer had gone through a myriad of attempts to correct it-head temp sensor, ecm, etc.

Not an issue on my 09.
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Teeps
Posted on Tuesday, October 18, 2011 - 07:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Try relocating the ECM. Knock on wood that seemed to fix my '06 Uly's problem.
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Bike_pilot
Posted on Wednesday, October 19, 2011 - 08:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

DV have you verified whether the engine is actually getting hot enough that it is "supposed" to skip-spark? Maybe something is wonky in the skip-spark logic and it is going into skip-spark too early.

good luck!
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Etennuly
Posted on Wednesday, October 19, 2011 - 10:21 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

My'06 started doing it regularly with the installation of a new fan at 20,000 miles after the original went up in smoke 600 miles from home.

The original fan did do the run/skip a few times on long up hills on hotter days. But after the new fan it was like all of the time.
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Darth_villar
Posted on Wednesday, October 19, 2011 - 10:23 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Unfortunately I don't have a palm pda to record all the time. And I haven't recorded 30 minutes + data. I know that it is plenty cool to be able to accelerate WOT without ping, which is a big deal in Phoenix. I have NEVER skip sparked before ping in normal/non highway riding. I wish Phoenix had 93 octane, real gas, no ethanol :/

The only thing that makes logical sense to me, is that the load in the ECM from the fan running at high speeds (redundant, perhaps additional load) is messing with the ECM somehow. If I had the opportunity, and if I didn't already rewire it, I would have liked to observed the Ohms through the fan after extended highway riding to confirm my suspicions.
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Bike_pilot
Posted on Wednesday, October 19, 2011 - 11:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Maybe try riding with a laptop in a bookbag. It'd be really helpful to know if the issue is too much heat or a wonky ECM. if the latter, check really closely for cracks. if the ECM is in the stock location the seat may well be mashing on the grey connector.

With the e.b.r. ecm the fan seems to run full blast almost all the time and mine doesn't skip-spark, though the '09 might have a different ECM setup in this respect. Maybe double-check that the grounds are all clean and well grounded, I know a wonky ground can make an ECM do weird things and the fan might put extra load on the ECM's ground.
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Towpro
Posted on Wednesday, October 19, 2011 - 01:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

recording the data before and including the SS event could be valuable. Maybe a sensor is breaking down causing the SS? or a sensor wire could be momentarily grounding out?.
Remember with computers, garbage (data) in = garbage out.

If I recall the file size is not very large. I used to put my (little) notebook inside my jacket over my chest and go out and ride.
I think you can then play it back picking what you want to see on the graph. Start a stop watch the same time as you start the recording. SS starts, look at the stop watch, ECMspy times on graph should match pretty close.

I know I have fixed some VW Turbo Diesel problems with this method that were pretty hard to uncover. (but driving a car it is easier to hit the correct key to "mark" the recorded event).
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Darth_villar
Posted on Wednesday, October 19, 2011 - 02:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If I get the time, which is unlikely, I will see what I can do. I don't know for certain that the hard wired fixed skip spark.

It is still in the 90's here, but I don't have time to ride other than to school and such :/ If I get a couple hours this weekend I will test to insure SS is gone. If it is completely gone, then the only thing it can be is a fan related problem.

I don't know where the fan ground is, but I will look for it as well. Otherwise it should be safe to suppose that something about the fan being on traveling xx speed for xx time is causing something to happen.
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Rr_eater
Posted on Friday, October 21, 2011 - 11:06 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Darth

The fan is supplied positive voltage at all times. The ground side of the fan is switched by the ECM directly. It does this so it can control high and low speed, by how fast it switches that ground.

SO, supply a ground, not positive, to the ground side of the fan wiring, and the only after effect is a CEL, but you know what that is for if the switch is one.

Currently working on a way to LIE to the ECM about mine being that way, brother is finishing up a diode switch circuit, should work awesome!

YMMV

Bruce
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Darth_villar
Posted on Friday, October 21, 2011 - 12:00 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Excellent Rr, let me know how it works out!

I'm most likely going to reprogram my ECM so that it never tells the fan to turn on. That way I can run a small wattage high ohm resistor to fake the fan being there. As long as the ECM never actually wants to turn the fan on, I should be in the clear.

I need to get a decent DMM dangit. I want to measure the current supplied when not in use, and likewise the voltage and ohmage.

Also, it has been a while since I have messed with my hex code, but I tried turning the "time to retest fan" byte to zero milliseconds, but it didn't work :P

(Message edited by darth_villar on October 21, 2011)
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Rr_eater
Posted on Friday, October 21, 2011 - 01:42 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Well

If you set the time to retest to zero, then in theory (of mine) you are actually telling the ECM to check it constantly maybe? All the ecm wants to see (again, a theory of mine) is coil feedback through the fan. I was thinking of using a bosch relay, and wiring it to the positive and negatine sides of the relay's coil driver, should be about the same. And then, if it did try to turn on the "fan", it would see the relay's inductive resistance and think the fan is on. AGAIN, just a theory of mine.


I have measured voltage and current for the fan, it was about 5.5 amps in low (11.3 volts) and 6 something in high (battery voltage). I do not think you can check the ohms, as it is a SMD FET circuit (I believe) in the ECM, and as such just shows open when not driving the fan motor.

Bruce
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Darth_villar
Posted on Friday, October 21, 2011 - 03:03 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I want the reading when the bike is running, but fan not active. It has to send some type of test charge. If I can emulate that with a proper resistor I *should* be in business... maybe :P

I thought that might be the case about setting the value to zero, not sure you can set a null value in hex...

I'm going to keep trying stuff, thanks for the info Bruce.

You have a good point about the coil driver, that sounds promising. I will be taking a circuits class next semester, so maybe I will learn something useful there
Phil

(Message edited by darth_villar on October 21, 2011)
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Reepicheep
Posted on Friday, October 21, 2011 - 03:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Again, did you check / replace the head temperature sensor?


quote:

The fan is supplied positive voltage at all times. The ground side of the fan is switched by the ECM directly. It does this so it can control high and low speed, by how fast it switches that ground.




That probably is how it is hooked up, but that's not why. They probably did it that way because it is much easier to design a MOSFET that can ground a circuit with an applied positive voltage... than it is to design it to add a V+ to an already grounded circuit.

If you get to MOSFETS next quarter, you will see why (Hint: VGS min).
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