This will be something that is more an more common, already is, as time goes on.
I'll use this thread to:
1 - track what category of bikes seem to have the issue - seems obvious the oldest bikes will have this first but maybe not.
2 - track the symptoms (FI codes) and trouble shooting steps before taking the big step towards a new ECM
3 - Discuss possible workarounds.
Also, no one here is an expert in spite of what they may think and a forum exists to discuss subjects and collaborate on those subjects. Anyone that does not adhere to that level of collaborative respect will be banned from this thread and possibly more.
I'll try to keep this thread updated as we move forward.
Symptoms:
- FI Code 26 - Right Knock Sensor - this is the code most will get and sometimes it is the sensor.
- Other FI codes have also appeared but 26 is the is the common one
- Reduced gas mileage, more heat.
Troubleshooting/Causes:
- HERE is a link for checking and resetting the code
- FI Code 26 - Right Knock Sensor - this is the code most will get and sometimes it is the sensor.
- The Honda 070MZ-MCA0100 ECM, Test Harness currently goes for over $2000 and there's probably other proprietary software you can't get unless you're a dealer
- Some have said the ECM fails due to age, heat, moisture, vibrations, etc... basically external environmental affects.
Solutions/Workarounds:
- Repair or Refurbish options - The ECM is sealed therefore not typically something serviceable.
- Replacement ECMs are currently anywhere from $600 to $1300 new, cheaper on ebay but you don't know the history and impossible to check if it has issues. Also, pre 2008 ECMs are tough to find.
- 2008 and newer ECM Part number - 38770-MCS-R12
- 2002 thru 2007 ECM Part number - 38770-MCS-L01 - Police version (38770-MCS-A31) will have a 120mph speed limiter
- A member noticed: "The only time it flags a light is when I push it over 4000 rpm in high gear. It kicks the timing back as soon as it flags the light, and that brings more heat and poorer mileage. Anything below that rpm in high gear and its fine. I can run it up red line through the rest of the gears, no problem."
- Manufacturers typically have to keep making replacement parts for 10 years after the last model - not sure how stringent that is but could be a big issue in a few more years as parts become more rare.
- It may be impossible for a company to create a replacement ECM or some type of bypass to fool the ECM into thinking all is ok as the market is a small one and the development effort will probably never be met.
- It's also possible the code 26... might be an electrical short and an accurate code, however that short may be what takes out the ECM. The knock sensors are close to the exhaust headers and the wire insulation doesn't last long in those areas, check yours as it may just crumble... perhaps some heat tape in that area will be a preventative maintenance issue?
- Also one possibility is some wire that has nothing to do with the knock sensor corrodes and grounds/shorts out and the knock sensor portion of the ECM is just the weakest path and that kills the ECM so the knock sensor could be a false indication of what is happening.
I'll use this thread to:
1 - track what category of bikes seem to have the issue - seems obvious the oldest bikes will have this first but maybe not.
2 - track the symptoms (FI codes) and trouble shooting steps before taking the big step towards a new ECM
3 - Discuss possible workarounds.
Also, no one here is an expert in spite of what they may think and a forum exists to discuss subjects and collaborate on those subjects. Anyone that does not adhere to that level of collaborative respect will be banned from this thread and possibly more.
I'll try to keep this thread updated as we move forward.
Symptoms:
- FI Code 26 - Right Knock Sensor - this is the code most will get and sometimes it is the sensor.
- Other FI codes have also appeared but 26 is the is the common one
- Reduced gas mileage, more heat.
Troubleshooting/Causes:
- HERE is a link for checking and resetting the code
- FI Code 26 - Right Knock Sensor - this is the code most will get and sometimes it is the sensor.
- The Honda 070MZ-MCA0100 ECM, Test Harness currently goes for over $2000 and there's probably other proprietary software you can't get unless you're a dealer
- Some have said the ECM fails due to age, heat, moisture, vibrations, etc... basically external environmental affects.
Solutions/Workarounds:
- Repair or Refurbish options - The ECM is sealed therefore not typically something serviceable.
- Replacement ECMs are currently anywhere from $600 to $1300 new, cheaper on ebay but you don't know the history and impossible to check if it has issues. Also, pre 2008 ECMs are tough to find.
- 2008 and newer ECM Part number - 38770-MCS-R12
- 2002 thru 2007 ECM Part number - 38770-MCS-L01 - Police version (38770-MCS-A31) will have a 120mph speed limiter
- A member noticed: "The only time it flags a light is when I push it over 4000 rpm in high gear. It kicks the timing back as soon as it flags the light, and that brings more heat and poorer mileage. Anything below that rpm in high gear and its fine. I can run it up red line through the rest of the gears, no problem."
- Manufacturers typically have to keep making replacement parts for 10 years after the last model - not sure how stringent that is but could be a big issue in a few more years as parts become more rare.
- It may be impossible for a company to create a replacement ECM or some type of bypass to fool the ECM into thinking all is ok as the market is a small one and the development effort will probably never be met.
- It's also possible the code 26... might be an electrical short and an accurate code, however that short may be what takes out the ECM. The knock sensors are close to the exhaust headers and the wire insulation doesn't last long in those areas, check yours as it may just crumble... perhaps some heat tape in that area will be a preventative maintenance issue?
- Also one possibility is some wire that has nothing to do with the knock sensor corrodes and grounds/shorts out and the knock sensor portion of the ECM is just the weakest path and that kills the ECM so the knock sensor could be a false indication of what is happening.
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