ST1300 ECU-Knock sensor problem

Just reading through this post. I can't pretend to have any experience of the knock sensor problem, but I'm intrigued.

In the first post, you say that the wiring harness has been repaired and the fault is with the ECU. Can I ask what made you come to that conclusion ? If I had a bike that had an obvious 'repair' in the wiring harness, I'd be looking at the repair for the source of the fault !

John
The oscilloscope traces I posted were measured at the ECU so proves the sensors and wiring are fine. The fault post you referenced was repaired by an ECU replacement. So I am just trying to find the cheapest way to replace my ECU, the American ECU looks the cheapest but there is the wiring harness issue. I am fairly certain it can be done I was just interested if it had done by anyone on this forum.

Regards

Shaw
 
Has anyone with this issue and replaced the ecm to resolve it ever opened up the old ecm to find if this is maybe a certain cold solder joint or some obvious issue with the knock sensor signal trace(s)? Just curious as I've seen this issue come up more than a few times here.....
 
Has anyone with this issue and replaced the ecm to resolve it ever opened up the old ecm to find if this is maybe a certain cold solder joint or some obvious issue with the knock sensor signal trace(s)? Just curious as I've seen this issue come up more than a few times here.....[/QUan do OTE]

Hi
The box looks very sealed to me but I guess you can get in it. There are people out there who claim they claim they can repair ST1300 ECU's, I'm a bit sceptical, anyone with any experience of this?

Cheers
Shaw
 
I found a motorcycle speed shop that said they wipe and reprogram ECU all the time. $200 in So Cal, likely less in other parts. Obviously for fuel and speed but why not for this thing also. I was wondering if they could speed up the refresh rate on the mpg read out, just because.
 
Has anyone with this issue and replaced the ecm to resolve it ever opened up the old ecm to find if this is maybe a certain cold solder joint or some obvious issue with the knock sensor signal trace(s)? Just curious as I've seen this issue come up more than a few times here.....
If you clear the code, how long does it take to come back? It's possible that there is a glitch in the sensor that may happen cold, warm or hot. If there are 2 knock sensors switch them and see if the code follows the sensor or stays on the same bank.
 
If you clear the code, how long does it take to come back? It's possible that there is a glitch in the sensor that may happen cold, warm or hot. If there are 2 knock sensors switch them and see if the code follows the sensor or stays on the same bank.

Hi

The fault is very repeatable, as soon as it is reset all you have to do is rev the bike above 3800rpm for more than 10 seconds. I can do this in the garage with the oscilloscope connected and can see that both knock sensors are 'normal' as the ECU faults.

Regards

Shaw
 
Hi

The fault is very repeatable, as soon as it is reset all you have to do is rev the bike above 3800rpm for more than 10 seconds. I can do this in the garage with the oscilloscope connected and can see that both knock sensors are 'normal' as the ECU faults.

Regards

Shaw
my experience with car ECM faults are mostly drivers. I cant remember when the ECM could not read an input signal and it does happen. Since both knock sensors are the same I would just switch them just to be sure. Can't hurt, will not take very long and would only verify your diagnosis.
 
Hi

The fault is very repeatable, as soon as it is reset all you have to do is rev the bike above 3800rpm for more than 10 seconds. I can do this in the garage with the oscilloscope connected and can see that both knock sensors are 'normal' as the ECU faults.

Regards

Shaw
Also I remembered something, the signal from the knock sensor changes when a knock occurs. The ecu will advance the timing to get a knock. You need to create a knock and compare both signals. You are looking at a static signal. When testing knock sensors in autos (early knock sensors) at about 2000rpm observe the timing and watch for it to retard when hitting the block with a hammer. The same should happen. The piezoelectric diode voltage will increase as the vibration changes. Smack the block with a hammer and watch your signals.
 
Hi all

Thanks for all the feedback and tips. I have now taken the bike to my local dealer and he has confirmed it is an ECU fault. They have recommended a firm called Carmo based in the Netherlands to do a repair. I am going to go for this and I will hopefully post with good news when I get it back.
 
Hi Shaw,
I have the exactly same problem.My 2004 also with H.I.S.S. (I'm getting FI code 25). I consider ECM fault, bike has only 18000Km (genuine) on the clock, no knock sensors connectors melted or corroded (they are not even dirty!). Under 1 ohm resistance between the cap and the ECM conne. (colours of the wires: Left sensor-Blue/Red,Right sensor-Black). I'm planning to run new wires from ECM harness to knock sensors, so I will be able to swap the sides to see if fault code change to 26. If not - then what, what else could cause this mystic fault?
Did you went for Carmo? Did you solved your FI light issue? I'm so disgusted, I own the bike for 2 months (1500Km) and until last week no problem at all. I still don't believe that the engine or knocks sensors could be "faulty" after 18000Km, so far my highest rpm was 6000 (that's how brave I'm!) ....to be honest: What could be the fault in the ECM which is fully working (worked) apart that FI shows code 25 above 4000 rpm. Bad Caps, leakage, cold joint? What else on circuits that operates in very low level voltages?
I rang to two authorised Honda service centers, here where I'm - Czech Republic. Their approach: Well it could be complicated and probably beyond value of the bike!!! I have paid more than 6000EUR two months ago for this bike!,... we don't have the service harness and tools for your bike and that age!!!...so if FI shows faulty know sensor, we will replace it and then we will see (they don't tell you that it will be at your cost)....try another Honda service. No, they don't wanna touch me bike, looks like nobody here have any experience dealing with St1300 neither this kind of issues. I now that Czech police forces had a few o these, until they have been replaced by BMW. I saw police one recently, passing by. Where they have been serviced? Or they (service centers) just swap the tyres and changed oil? This country drives me mad! I now it's not a country, but the people who living here and their "culture" which is still under bigger influences from growing russian population especially in Prague...English couldn't be moore accurate: Culture clash! Suddenly I have Czech passport hence I was born and grown here and our family lives here since we know, but I don't see many points that connects me with them (Czechs).
Back to topic: I have to help my self! Any remarks to my conclusions?
Did the Carmo fixed and returned "your" ECM or just ECM which has been factory refurbished (swapped refurbished unit) - I'm asking about H.I.S.S. functionality/pairing with keys?
Hopefully this weekend I will see if my theory makes any progress (swapping sides to see what the ECM will report)
Sorry to be novelist...any suggestion, reports, ideas welcomed!
Drive save!
 
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Anybody on this board had his bike serviced at JK Performance here in Houston (/Missouri City)?

I stopped by to check how familiar he was with the ST1300: He asked if mine was throwing the 25/26 code....!

He talked about servicing one that was displaying the code and swapping the ECU didn't help. So he was open to suggestions.......Wondering if the owner of the bike is on this board.

Honda indicated to JK they were aware of the issue.....but had no insights on the cause....and unsurprisingly they never gave him the impression that it was on anybody's list of problems to solve, or would ever be.
 
For those affected by the code 25 / 26
Bellow is an reply from the Carmo.nl


Hi

Yes we are very experienced with the fault codes 25/26 we can also test and confirm that if you like but chances are very high that the ECU is defective.
We have tried to repair those error unfortunate after days of research we had to conclude that repairing is impossible. Replacing is your only option.

If you can find a second hand unit we can help you copy your key codes to the new ECU.

Hopefully this has answered your question, if you have any please feel free to contact us.

Kind regards.

Kevin van Hout

Post- en verzendadres / Shipping address (for shipping with regular post):
Postbus 393
5700AJ Helmond
The Netherlands

Bezoek- en vestigingsadres / Company location:
Rooseindsestraat 54a
5705BV Helmond
The Netherlands

Dear Carmo,
Im in struggle with my Honda ST1300 ECM 38770-MCS-G02 with H.I.S.S., which shows fault code 25 (Knock sensor). Many ST owners experiencing the same fault code (or 26 - Knock sensor on the orther side) - apart from this fault code ECM behaving flavelessly.

My questions are following:
Did you have any previous experience with these specific fault codes 25 / 26?
Do you thing that you could test and confirm these circuits are faulty and fix ECM with these specific fault codes or you would recomend to buy whole new ECM in this situation.
Do you also need a Key with H.I.S.S chip (paired) to be shipped together with ECM for repair?

Thank you very much for understanding!

Really frustrated ST rider.
 
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Will a non H.I.S.S. ECM work with a H.I.S.S system?

If so, maybe you could find a US model on ebay to replace yours. I'm sure the H.I.S.S. light will stay on though....
 
Will a non H.I.S.S. ECM work with a H.I.S.S system?

Not directly. North American bikes have a split in the wiring harness that provides power to the ECM on two pins and an ECM that becomes a doorstop unless power is present on both. For a number of other Hondas, the rest-of-the-world wiring harnesses only have one pin providing power. There's a guy in Australia who's added the extra pin to his harness and used a North American ECM successfully. I haven't been able to confirm that this is the case for the ST, but it seems like they'd do the same thing across the board. Similarly, the rest-of-the-world ECMs expect the HISS hardware and a valid key, which makes them useless on North American bikes.

--Mark
 
Anybody on this board had his bike serviced at JK Performance here in Houston (/Missouri City)?

I stopped by to check how familiar he was with the ST1300: He asked if mine was throwing the 25/26 code....!

He talked about servicing one that was displaying the code and swapping the ECU didn't help. So he was open to suggestions.......Wondering if the owner of the bike is on this board.

Honda indicated to JK they were aware of the issue.....but had no insights on the cause....and unsurprisingly they never gave him the impression that it was on anybody's list of problems to solve, or would ever be.

I've had JK work on a couple of my bikes over the years, but the only thing that he has done for my ST so far has been to replace rear wheel bearings, but I may need his help trouble shooting mine if I have any problem doing it myself or just want to leave it to a pro to find the problem. JK worked on both of my Suzuki bikes over the years and balanced a few tire/wheel assemblies back in the day when I replaced my own tires. I've known JK for at least 25 years and he is an excellent mechanic IMHO.
 
I've known JK for at least 25 years and he is an excellent mechanic IMHO.

Thanks for the recommendation. He seemed very knowledgeable but I was somewhat taken aback when he mentioned that running Diesel Oil would be a good idea......
 
Thanks for the recommendation. He seemed very knowledgeable but I was somewhat taken aback when he mentioned that running Diesel Oil would be a good idea......

Sounds like a very knowledgeable person, and yes, running diesel oil is a very good idea in motorcycles.
 
An update to the case: MY vs FI on ST

1) New bypassed wires from ECM to the Knock sensors > FI 25
2) Knock sensors swapped > FI 25
Just out of curiosity3) Left wire disconnected > FI 26!? (Blue/Red wire on my ST)
4) Right wire disconnected > FI 25 (Black wire on my ST)
out of despair
5) Connected againg as it should it be (using "bypass" wires) > FI 25
6) All reconnected back to (original) wires of bike harness > FI 25

So that means no progress at all - still error code FI 25

What next?
:mad:
...cleaning 5 T way connector....injectors...just to be sure???
Fault appeared out of the blue, on a bike vith 18000km, no oil drop, no rise in petrol consumption (shows 6.4l/100Km), apart from FI 25 all seems to be OK.
I can't help my self, but more and more convicted that ECM is Faulty...

Any idea, trick or miracle to try?
HELP!
ECM (38770-MCS-G02) for sale?

I'm disgusted by all of this..and I broke neutral sensor by accident...

Looking for rope and strong bench...Im done!
 
My local Speed Shop routinely wipes and reprogram the ECM. They do it mostly for air fuel mixture, timing, the usual stuff but why not wonder if the wipe and reprogram would fix this problem.

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