Right... for a bike that isn't being produced anymore and that segment is decreasing over time... not an impossible task but I wouldn't bet on it. Too bad Honda gave up on the ST...
FI Code 25 Knock Sensor Issue - HEALED!
- Thread starter Khav
- Start date
You think the ST brain has Alzheimer, me think stroke!
Expert shops have attempted troubleshooting with this baby on the bench which shouldn't be too noisy of an environment?
Is the ecu replacement just a “ plug and play” .? my bike doesn’t have ABS , do I need to get a non ABS ecu ?
Andrew Shadow
Site Supporter
Yes, plug and play.
No, ABS or not doesn't matter.
No, ABS or not doesn't matter.
Hello,
So did anyone fix error 25 in ECU ? I have one, for 3 days I has glad to run it without FI în any rpm range and then appears again when I rev it more than 2500rpm.
Those ecus is possible to repair with this problem ?
With FI light the engine run enriched ?
So did anyone fix error 25 in ECU ? I have one, for 3 days I has glad to run it without FI în any rpm range and then appears again when I rev it more than 2500rpm.
Those ecus is possible to repair with this problem ?
With FI light the engine run enriched ?
Hi @Paraoanu Iulian !
Sorry to hear you're experiencing this problem. I have not heard of anyone else experiencing this problem below 4,000 rpm. There are a few things you can do to verify whether the error code is truly the result of a faulty ECM. However, the main causes of a "false" knock sensor code to be triggered are usually (a) insufficient battery voltage, (b) damaged wiring between the knock sensor and the ECM, and (c) loose ground connections.
I experienced this problem on my '05 ST13 a couple of months ago. After going through the process outlined in the Honda SM, checking the grounds, battery voltage, and disconnecting every accessory that was not installed by the factory the code persisted. Ultimately, I located a NOS ECM designed for US police bikes in Japan, had it shipped to the States, and installed it. The new ECM solved my problem. Sadly, Honda no longer makes pre-2008 ECM's, so finding a used one, let alone a new one, is extremely difficult.
I recommend that you contact @Igofar a.k.a. Larry, because he is a true ST whisperer. Send him a DM, and he will timely respond. Because he is located in Arizona, he's on Mountain Time. As I write this, the time where he lives is 7:38 a.m. If your calling plan allows for calls to the US, he'll give you his number and walk you through the process. Larry is retired, and unfortunately (for you) his calling plan does not extend outside the US.
Again, I'm sorry to hear you're having this problem. Hopefully, the problem is not with your ECM. Wishing you the best.
Chris
Unfortunately, the shops that have looked at failed ST1300 ECUs so far have all said they couldn't repair it.
Typically, with the FI light on, riders are reporting a slight loss of power and using a bit more fuel, about .5 L/100km more.
So you could think that it runs richer, at least most of the time.
Some ST Owners have been riding with the light on for years and their bikes are still going.
Be careful in your case though, as you have not confirmed yet this is not a real knock sensing issue that needs to be addressed. As @Buckeyechris mentioned, when the fault is related to the ECU, it appears at RPMs higher than the 2500 you are observing, you'd have to rev it up over 4200 RPM to trigger the fault.
If it is a real knock sensing issue, you could cause damage by keeping it running the way it is.
Thank you for your answer!
I don't think that I have a real knock because the engine sound normal at all revs, last time I has put 100 octane gas, the sparkplugs was look good on inspected. The only posibility to self ignition is if I have somme carbon on pistons or exhaust valve. I has put some additives in gas to clean it.
Hello Chris,
Thank you for your time to write to me !
În the first part it has start to light every time at 2500rpm. After one week runing like this the rev at start FI lighting begin to be higher and în last day it do not start light at all. And then I put my motorcicle în a electrical revision. After this I has run it happy 3 days without FI failure. In next day the light FI again but this time I think that is more than 2500rpm . It coud be 4000.
Code 25/26 is a SENSOR circuit issue, not linked to your engine knocking or not.
If you have problems troubleshooting the sensor circuit itself, as Chris suggested, @Igofar (Larry) might be able to help you with that. Larry has fixed some bikes with the 25/26 issues without having to replace the ECU.
But unfortunately, in many cases, the ECU is at fault, thinking the sensor is not working when in fact the sensor is OK.
To contact Larry directly, click on his avatar further up in this thread and start a conversation.
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- Joined
- Mar 18, 2006
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- 3,017
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- 70
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- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2024 Miles
- 000679
Warning. I don't know what I am talking about here.
But. I have observed that when (a long long time ago) I have taken my ST1100 or 1300 to be checked over by people who do know what they are talking about, that one of the things that they have done is start the engine and hold the throttle open for a while.
I assumed that they were listening for something. But it seems that they might have been trying to trigger a fault code.
I have seen a few numbers quoted in various places - one for prior to balancing throttle bodies. But without looking up the details, figures of around 2,500 and 4,000 spring to mind . Please remember, I don't know what I am talking about, so these figures are probably irrelevant. It would be useful to know what rpm triggers what failure codes, if indeed the parts have failed.
It seems that the fault is triggered under certain circumstances, and once detected, the ECU goes into an emergency 'thick'mode - like bikes used to be. The tuning was at best a compromise. The intelligent mode is where readings from sensors dictate how the tuning should be adjusted while it is moving. If the engine is knocking, then lets have a bit more fuel please. If it isn't lets get less fuel in the air mix. But it only goes into the default mode when it recognises that there is a fault. Evenso, it will be more intelligent than the old 'thick' mode, resorting to settings obtained from a table - a map - which gives the settings to adopt at certain revs / gears / speed / whatever.
There are other ways that the fault code can be reset. One example is after balancing throttle bodies, where the deliberatly imposed fault can be reset using a procedure which involve starting the engine without touching the throttle. There may be other ways for resetting the Ecu knock sensor code.
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My first 1300 had a really weird issue. If I had been riding along without any throttle movements for a long time - eg tootling along at 60mph in high gear - and then came to a roundabout, slowed, changed down as the speed dropped, and then opened the throttle to balance the lean, and lift me out of the corner, I got nothing - except An odd sensation from my seat as I realised that I might be about to fall over.
Someone told me - and he was one of the management team at Honda Uk - that the engine management changes mode in such circumstances, and needs information to make it 'wake up' and become more responsive. Ever since then I have gone against the recommended approac to roundabouts, and changed down through the gears, blipping the engine and using the gears to bring the bike down to speed. And the bike never did that hesitation trick again.
Back to the plot - the manual says that the engine runs normally if the 25/26 fault code is thrown. I'm wondering if it is the fault diagnosis that is wrong, and that if the fault can be reset, it works properly until the next time that 4000 rpm is reached.
Just musings.
But. I have observed that when (a long long time ago) I have taken my ST1100 or 1300 to be checked over by people who do know what they are talking about, that one of the things that they have done is start the engine and hold the throttle open for a while.
I assumed that they were listening for something. But it seems that they might have been trying to trigger a fault code.
I have seen a few numbers quoted in various places - one for prior to balancing throttle bodies. But without looking up the details, figures of around 2,500 and 4,000 spring to mind . Please remember, I don't know what I am talking about, so these figures are probably irrelevant. It would be useful to know what rpm triggers what failure codes, if indeed the parts have failed.
It seems that the fault is triggered under certain circumstances, and once detected, the ECU goes into an emergency 'thick'mode - like bikes used to be. The tuning was at best a compromise. The intelligent mode is where readings from sensors dictate how the tuning should be adjusted while it is moving. If the engine is knocking, then lets have a bit more fuel please. If it isn't lets get less fuel in the air mix. But it only goes into the default mode when it recognises that there is a fault. Evenso, it will be more intelligent than the old 'thick' mode, resorting to settings obtained from a table - a map - which gives the settings to adopt at certain revs / gears / speed / whatever.
There are other ways that the fault code can be reset. One example is after balancing throttle bodies, where the deliberatly imposed fault can be reset using a procedure which involve starting the engine without touching the throttle. There may be other ways for resetting the Ecu knock sensor code.
-------
My first 1300 had a really weird issue. If I had been riding along without any throttle movements for a long time - eg tootling along at 60mph in high gear - and then came to a roundabout, slowed, changed down as the speed dropped, and then opened the throttle to balance the lean, and lift me out of the corner, I got nothing - except An odd sensation from my seat as I realised that I might be about to fall over.
Someone told me - and he was one of the management team at Honda Uk - that the engine management changes mode in such circumstances, and needs information to make it 'wake up' and become more responsive. Ever since then I have gone against the recommended approac to roundabouts, and changed down through the gears, blipping the engine and using the gears to bring the bike down to speed. And the bike never did that hesitation trick again.
Back to the plot - the manual says that the engine runs normally if the 25/26 fault code is thrown. I'm wondering if it is the fault diagnosis that is wrong, and that if the fault can be reset, it works properly until the next time that 4000 rpm is reached.
Just musings.
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@Paraoanu Iulian ,
If the problem is intermittent as you describe, you might get lucky because it sounds like a voltage irregularity that is triggering the error code. Like @MidLife recommended, get with @Igofar , and I'll bet he can help walk you through the diagnostics. Hopefully, its something as simple as dirty battery terminals, loose ground, or a nearly dead battery.
Precisely how mine behaved. Would reset at every shut off. Then relight over 4200 RPM.
Some have resolved the error codes by replacing a weak battery. The theory is that the ECM is sensitive to voltage irregularities. If you have ruled out your battery, the next check would be to verify the integrity of the wiring between the knock sensor and the ECM. Some have found the wiring between the sensor and ECM had been damaged. They either replaced the damaged wiring or completely ran new wiring between the sensor and the ECM to resolve the issues.
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General Description
The knock sensor is mounted on the engine block and detects engine knocking. The vibrations caused by the knocking are converted into electrical signals through the piezo ceramic element. The engine control module (ECM)/powertrain control module (PCM) controls the ignition timing based on the electrical signals. If the signals from the knock sensor do not vary for a set time, the ECM/PCM detects a malfunction and stores a DTC.
I have never read a diagnostic flow chart for this code that stated test or replace battery. There is no battery or 5v reference voltage to that sensor. All the engine sensors are voltage sensitive if the voltage was out of range I'm sure other codes would be there.
RobbieAG
Robert
Not sure ST P/Ns are going to help him much as he seems to be on a Blackbird. He may be better off inquiring on the BB site. Seems like @Chris09 has a BB as well and might be able to direct him to relevant ECU threads on the BB site.
- Joined
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- Coquitlam British Columbia Canada
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I see I have a message from Paraoanu but unfortunately I don't speak the language. I agree with Midlife maybe someone who can translate will get him onto that forum. I have a thread there entitled first impressions where he can see some good feedback in response to my ECU knock sensor fault from members there.
Gus1300
Site Supporter
Since you are familiar with the weaving solution, I assume you are already on the blackbird cbrxx.com website. I have a thread there titled; first impressions that revolve around a few topics, but show some feedback we got from some of the members there. Mine is an 03 with only 4,400 miles and has never had any accessories. I didn't do the loom repair, but I removed all the plastic, disconnected and cleaned various ground points [removed paint from the one under the tank base] and in the end my problem might just have been the battery [8,8 Start VDC. vs 10.35 VDC with the new one] and insecurely mounted ECU. I've ridden it the last two days about 160 or 170 miles and everything seems fine, I've had it at 6,500 on the stand a few times but don't think I've gotten it over 5,000 while riding it. The ST ECU seems to be 4,000 or 4,200 which sets up the knock sensor failure, while the most commonly quoted point on the CBR1100 seems to be 5,000 rpm. Here in Canada the Honda dealer told me ECUs are still available for the Blackbird at $1,830.00 Canadian.
(I'll save everyone the trouble of having to do it themselves)
(I'll save everyone the trouble of having to do it themselves)
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