| Author | Message | ||
     Cataract2 |
I know there was some talk back about the low fuel light coming on even though you have a full tank. Wondering if anyone got a solution to this? I still need to take mine into the dealership as they got the service bulletin (I read it, but there was no answer on the one I read). | ||
| Marcodesade |
I am under the impression that getting them to replace the cluster with the 09 model solves the problem. | ||
| Carbonbigfoot |
Nope. My 09 CR does the same thing when it's cold. Rob | ||
| Tonedeath |
i thought that was the problem also but they replaced the cluster and still the peskey low fuel light burns on its like a tootsie roll pop the world may never know | ||
| D_adams |
I just had mine come on at 146 miles since the last refill, rode another 8 miles to get gas, filled it up, reset the trip meter and it wouldn't go out until I got about a mile away from the gas station. I was getting worried that it would stay on, but it did finally turn off. Average for this tank was only 35 mpg, but I blasted up over 120 a few times, just to feel the breeze.  | ||
| Dirty_john |
Gentlemen, had the same problem recently with my 09 1125R and cold fuel, the low temperatures over cooled the thermistor which reacts to the presence of otherwise of fuel, seems to be an issue with 08 bikes with 09 instrument clusters and 09 model year bikes, my dealer - Chested HD - very helpful - advised that there was a reflash available, since the reflash we have had some quite cold weather here in the UK and the CEL/LFL issue has not reoccured. | ||
| Anonymous |
Dirty John, please don't post half truths and misinformation. The LFL issue has nothing to do with the thermistor. It is a software glitch in the IC causing this issue. The software glitch comes from the amount of time the cluster is supposed to look for a LFL condition. Clusters without this issue check for LFL conditions for at least ten seconds before the LFL will come on while clusters with the issue will turn the LFL on anytime it sees an output voltage from the thermistor which is in the specified range for a LFL condition. The problem is induced during cranking when the starter pulls down the overall system voltage which then pulls the voltage across thermistor down to a point where it is indicating a LFL condition. Since the cluster is supposed to "see" a low fuel condition for at least 10 seconds before throwing a LFL this should not be an issue, but for the affected clusters it is. The best way to check to see if your cluster is affected is to check what software version you are running. For earlier clusters namely 08MY you will have to look at the sticker on the back, for 09MY you can check in the diagnostic menu by scrolling to the last screen. If you cluster version is anything below V6.1 you should get it a new cluster. V6.1 is the latest and greatest version for the cluster. Cold conditions do tend to induce this behavior more but the reason is the battery is colder and will have a higher voltage drop during cranking. | ||
| Cataract2 |
Thanks Annoymous. That explains it well. I'll take this to my dealer when I take my bike in for this. While we're on the topic of the clusters. Does the gear indicator for the 09 clusters work with the 08 bikes? | ||
| Anonymous |
yes | ||
| Court |
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| Jaimec |
Is this corrected by the 4th flash for the 09 clusters? That is a rumor I've heard and I want to verify. Thanks, | ||
| Anonymous |
Dealers do not have the capability to flash clusters. All they are doing is replacing the cluster with a newer one. | ||
| Jaimec |
Aha. Thanks. I've been plagued with an erroneous LFL and CEL since the temperature has dropped at the end of autumn till now. So the dealer actually has to replace the entire cluster, then? | ||
| Dirty_john |
Anonymous - condition reported as found and repeated on at least ten occasions resistance of thermistor found to be 2200 ohms, with a fuel temperature of 6 degree C -resistance found well outside of the expected range specified in the 09 Buell diagnostics manual - pity there have been no manual updates - why did I pay £50 UK for a manual I wonder - I followed the diagnostics to the letter including the posted error codes. Checks undertaken when not cranking the engine obviously, engine then started and warmed up.When "coolant cold" display ceased the IC LFL and CEL lamps then went out, resistance of thermistor measured as 1100 ohms at that time - within the expected range according to the manual.Heat transfer to the fuel had warmed the fuel significantly. As a commissioning manager of nuclear and pharmaceutical R&D plant for 26 years with more mechanical engineering qualifications than I can recall I think I know how to accurately report events. Local dealer had agreed my findings to the letter until they loaded the reflash and thankfully the problem disappeared, the bike had done under 100 miles at the time.Bike battery is always on a battery tender when not being ridden. I will accept your apology, I wouldn't change either my Firebolt of my 1125R for any other bike and would buy another Buell tomorrow without hesitation. | ||
| Jaimec |
Okay, so now we're back to the fourth flash fixing that annoying problem with the 09 clusters? I'm soooooooo confused... | ||
| Anonymous |
Dirty John. While I appreciate and believe all of the information you gathered is true, the fact that you represent it as the reasoning for the LFL issue is where I have a problem. The thermistor in both XB and 1125 bikes work off of the principal that when they are in fuel, they are cooled down thus causing the resistance of the thermistor to increase having a larger voltage drop across it. When the thermistor is out of fuel, it heats up and its resistance decreases causing a smaller voltage drop across it. The cluster is set up such that when it sees a low voltage (0-6V) it is in a low fuel condition. So while your "observations" are valid they have no relevance to the issue since the colder the thermistor is the higher the resistance pushing it further into a high fuel condition. The LFL stays on after false indication because part of the bug was intertwined with the diagnostics of the LFL sensor where certain functions won't be checked until after coolant temp is warm. That is why if you get a false LFL the light won't turn off until CT is warm and even then it takes an additional minute to reset after CT is warm since the cluster must see a high fuel condition for one minute before it will turn of the LFL. Also, if your dealer is telling you that he flashed your cluster he is lying to you, as I said previously the dealers do not have the ability to flash clusters. ECMs yes, clusters no. My point in correcting you was that I don't want riders replacing fuel pumps and/or thermistors when the real issue is the cluster. PS I will accept your apology. | ||
| Ccryder |
Anonymous I often wondered how those pesky little devils worked. Being a Mechanical Engineer, all that electronics stuff is Greek to me ;+}. Thanks again for the info. Neil S. | ||
| Bobup |
So if I have read and understand Anonys' last post. The LFL indicator sensor works by temperature....so wouldn't the tank heating up (we have had boiling fuel in the past, yes a reflash took care of some of that issue) while riding cause the sensor to indicate low fuel incorrectly or prematurely? (Message edited by bobup on February 25, 2009) | ||
| Anonymous |
No, the temperature that the internal components of the thermistor get to in a low fuel condition far exceeds the temp of the fuel during boiling conditions. | ||
| Zac4mac |
I've been here on BWB for about a year and a half and I've never had occasion to do this - Anony, I call BS. I've made the same measurements on my bike as Dirty_john. 08 R # 00154 with an 09 IC Stated range for the thermistor is 850-1400 ohms. Low Fuel comes on when thermistor is below 850 ohms. LFL AND CEL come on when thermistor is 2k-2200 ohms. Out of Range I just got "the most recent flash" last week. Last line in Diag Mode is SW 6.1 CAL 1.0 I still get this, have a B1005 historic DTC. Z | ||
| Anonymous |
Please feel free to disagree but at least state what it is you disagree with that I've said. Are you saying my entire post on how the cluster works is BS? As I stated before I don't refute John's observations or yours. What I refute is him saying the LFL issue is due to the thermistor, he is wrong. As for your bike, could your thermistor be out of range? Absolutely. Per your post though you say your LFL comes on below 850 ohms. Yes, the cluster is working as it should. As I said before, the lower the resistance the lower the voltage drop = low fuel light condition. Just because the thermistor is below 850ohms doesn't mean the cluster can't function as it should. The cluster is simply looking for a voltage in a specified range as I said earlier (0-6V). Your LFL and CEL comes on when your thermistor is between 2k-2200. Yes, your cluster is working correctly. This actually has nothing to do with your fuel level. The cluster has diagnostics for an open circuit condition on the LF sensor. An open circuit is the equivalent of infinite resistance. If a thermistor's resistance increases to the point where it looks like an open circuit, specifically the voltage drop across it is so large that the cluster can't tell if it is open or has a very large resistance, then the cluster will turn on the CEL and LFL to warn you that the thermistor might have malfunctioned or become open. I will reiterate though that this is a diagnostic function and not an indication of a low fuel condition. B1005 is the diagnostic code for an open circuit on the low fuel sensor, this makes sense. This whole thread began with someone asking about the LFL issue. The LFL issue is well known and even documented in a Tech Tip. Are you trying to say that its possible for the open circuit diagnostic to initiate under cold conditions? Sure, that's entirely possible but a whole separate discussion from the low fuel light falsely coming on. That's why in a diagnostic condition a check engine light comes on along with the low fuel light so that they are identified as two separate events. Cataract2 wanted information regarding why his LFL and LFL only was coming on when he had a full tank. At no time did he state he had a CEL nor anyone else before Johns post. Please explain what I have written that is BS or better yet explain how the cluster "actually" works. | ||
| Clarkjw |
Anon, you're good at responding to crap and barely acknowleging the real 1125r issues. That said, any help is good. HD dealers are usually of negative use. | ||
| Anonymous |
Clark, I myself try an help where I can. I apologize that I can't help with every issue or ones you deem important. | ||
| Ponti1 |
Anony, you have MORE than answered what was asked in this thread. Anyone indicating otherwise has not read from the start. THANK YOU!! Now, if you could just tell me where to send the check for Homecoming 2009, I'd be completely fulfilled! | ||
| Cataract2 |
Hm, I have had the LFL on and on one occasion the LFL and CEL on with Low Fuel Sensor fault. Looks like I have both issues. Well, solve the first one of the LFL first and see if all clears. Come on 09 cluster. | ||
| Clarkjw |
zomg, anony responded. Can you post in the fuel injectors thread and get us 08s the 09 flash to go with the new injectors. I doubt you'll respond to this, but I can hope. If you'd helped me with any of my Buell issues, you'd get a huge gift marked Anony to East Troy, not just a TY on an internet forum. | ||
| Dirty_john |
Gents, two points to close here - the 09 Buell factory diagnostics manual states that a resistance outside the specified range requires a replacement of the fuel pump sender assembly, why are manual updates not available over the net or via this forum or UKBEG? What other errors or mods have led to other sections of the manual being erroneous? 2). I am aware that the IC cannot be flashed but since the ECU reflash the problem has disappeared. I will check my IC issue number at the weekend. If there is an issue with the IC why has Buell MOCO not ordered a recall - or is this going to gone on for some time as has the clutch hydraulic fluid leak? - which to date I have not had a problem with but it is early days. There were many other 1125 owners who posted on this forum who had identical issues as mine with the LFL/CEL if you care to search. Safe riding | ||
| Dirty_john |
anonymous - thanks for your response, yes a thermistor works by a varying resistance due to cooling effect. the very cold fuel was increasing the resistance outside of the specified range hence the conclusion via the diag manual that the unit was defective, again the I will state that unless updates are issued for the diag manual it is next to useless - perhaps you can ask Erik to sort this out. | ||
| Dirty_john |
Anonymous - just thought on - from memory I seem to remember from the diag manual that the IC looks for the thermistor resistance within a specified range and if the resistance voltage range occurs outside of range this is why we were getting the LFL and CEL lighting up together with posted an error code as well. with a long lead thermocouple the fuel temp was about 6 degrees C with the measured resistance of 2200 ohms. When the bike was warmed up until the LFL/CEL went out the fuel temperature was about 12 degrees C and thermistor resistance around 1100 ohms. My garage has antifrost heaters that keeps the air temperature above 5 degrees C at all times. | ||
| Zac4mac |
Anony - my "BS call" was referring to the low battery explanation of the LFL coming on. This issue first got reported when a few of us with 08 Rs got 09 ICs. The only times I've heard of it, it was in conjunction with a CEL also. When My CT is between 149 and 165 dF I usually see LFL/CEL. My LFL functions properly, it comes on with about 1.3 gal left. I would like a solution to the LFL/CEL issue without leaving my bike with Service for diagnosis. Do I need a new IC? Do I need a new fuel pump/sensor ass'y? or Do I just have to put up with this until the weather warms up? Anony - at any rate, thanks for getting involved, that is the best part of this forum. Zack |
