ECU Repair?

Chris09 said:
It seems that just from reading submissions that in some instances the faults occur at a specific load / rpm and in others they might run for some duration and reoccur.
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It most commonly seems to happen at a sustained 4,000 RPM or over at full operating temperature- i.e. closed loop operation. If someone were to go for a ride and cruise below 4,000 RPM with only momentary RPM bursts above that threshold, it is possible that it may not appear for quite a while.
Chris09 said:
I guess the only two reservations I'd have with that idea might be whether or not I'm running the risk of creating a greater risk of component failure which could result in a fault while you're riding, and if the repaired ECU might cause a problem with the test bike.
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Quite a few people have been operating their ST1300's with this problem present and have not reported any adverse effects other than reduced performance when the FI light is on. My reservation in doing that for a prolonged period would be if there was a situation where a genuine pre-ignition (pinging) problem had developed and went undetected by the rider. In this scenario, the ECM is not correcting for the problem. If left for a prolonged period, is one running the risk of engine damage as a result?
 
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Daniel said:
One more point folks.

I am surprised at the replies I have received in this thread. I have been hanging around motorcycle forums for about 25 years (BMWMOA, Concours.org, HDforums.com, KLR650...etc)

I paid $3500 for my bike in 4/2016 with 26K, and I still, as recently as 3 weeks ago at a memorial/charity ride have people ask me if my ST is new. The bike owes me nothing, and I am in now way complaining I have to replace a ECU in a 18+ year old bike. The only thing I will complain about is the $813 cost for a new ECM.

That's where these forums have served me very well over the years. I have saved a boat load of money, and time because of the folks on these forums.

I am surprised at the replies I have received telling me why this won't work. I'm not stupid, I already know this is a low percentage play. But, what f I am right? I happen to know of two motorcycles that were repaired this way (one by yours truly), and a buddy and I repaired the ECU in his Yamaha wave runner this way. Maybe I can save the next guy $800 who comes to this forum to look for a solution for his intermittent 26 code.

My only decision now is whether I am going to pull my ECU and crack it open, or spend $800 for a replacement, then crack mine open. It's already a paper weight; why not, right? I guess the third option would be to replace mine, throw the bad one in the trash bin and go riding.

The original purpose of this post was to hopefully find someone who has attempted to open one of these.

I would like to add one additional question. I know some folks have come across burned/charred knock sensor wires; but has anyone actually had a bad sensor?
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I'm in the same boat with the code issue. Where did you find the $813 for the ECM?
 
I'm a retired bench tech and have been reading this and previous ECM-issue posts with interest. (Not a problem, of course, with my ST1100). Assuming the problem is internal to the ECM, and not with the sensor itself or the associated wiring, there are 2 major hurtles to the diagnosis and repair. They being, removing the packing sealant from the unit and diagnosing and repairing the electronic fault. From my experience, the first problem is, by far, the biggest. The sealant is
 
(uhm, my above post was partially cut off ... reposting)

I'm a retired bench tech and have been reading this and previous ECM-issue posts with interest. (Not a problem, of course, with my ST1100). Assuming the problem is internal to the ECM, and not with the sensor itself or the associated wiring, there are 2 major hurtles to the diagnosis and repair. They being, removing the packing sealant from the unit and diagnosing and repairing the electronic fault. From my experience, the first problem is, by far, the biggest. The sealant is very messy and very difficult to remove. Conversely, the electronic repair is often fairly straight forward.

With almost all the things I've worked that used the digital sealant, it was much more cost effective to simply buy a new part rather than spend time digging out the sealant to get to the PC boards and do the repair. In the case of a component that costs close to $1000, like the 1300's ECU though, it may be worth the effort. So, if someone has an ECU that they are going to through out anyway, I would be interested in taking a look at it to see if it's feasible to somehow flush/chip away the sealant and then diagnose the electronic issue.
 
Someone mentioned above that the ECU's on a motorbike are subjected to horrendous conditions with heat variations, dampness, vibration, etc. I recently had a problem with a 'fluid' leaking out of the (very basic) ECU on my CB750, and on further investigation/online research I discovered that Honda flood the ECU box with a resin after assembly to stabilise heat impact, exclude dampness, and reduce vibration. I do not know if this applies to all ECU's but before you start dismantling it might be worth checking to see if it can actually be worked on, or if it is a block of resin that would be a real PITA to remove. Apparently the resin does break down over time and that is when it starts to leak out of the casing like it did on my bike (1992 model - so it lasted nearly 30 years, the past 10 years in the tropics).
 
This is kind of where I sort of take the view of these bikes may be at or near the top of the evolution graph [and what goes up seems to come down] in terms of overall utility and durability.

In the early 90s when I had no money, a new honda was 20 Canadian and a new Cavalier [Chev anyway] decently optioned was 16.5, I was persuaded / convinced to buy the Honda and here in western Canada nearly thirty years later you still see many of the first generation of FI cars on the road, we pounded ours for twenty five years and 385 kilometers. Whereas I was a younger man when you could still find any significant number of those GMs of the same period [and I love GM, I've got three of them].

Now we've got this "right to repair" movement whatever you wanna call it going on, which I think reflects a couple of things [very] relative to motorcycles.

The first is, why are there so many beautiful brand new looking refrigerators in the dump?

What really puts my theory / observation into context is Dodge Vans, my Multi-Port FI [hmmm.... multiport....] 27 year old version, I've had them all since '71 as either my own or service vehicles, you could always fix them, but it's looking like it will be manufacturer's support that will be the catalyst when this one goes to the crusher, maybe over the inability to justify the cost of a windshield wiper assembly or a vent window assembly.

I think it's become an early 2000s change in the manufacturer's position; they know they can build things to last, and / or be easily serviced or rebuilt, they've by and large all got on board and even lesser quality vehicles seem to be pretty good. But... what do they do when the market gets saturated?

So, if they can built it to last indefinitely, why not bring the goal post a little closer, closer, no no back a bit... right... there. Fifteen years. We'll build everything to a fail / unreliable date of fifteen years, we'll support the warranty and the product to that point, no problem, the buyer will still get good resale, the second owner will learn at his own peril, but have no recourse anyway, while the original buyer, still in his dream like trance heads right back into our dealership.
 
Andrew Shadow said:
Quite a few people have been operating their ST1300's with this problem present and have not reported any adverse effects other than reduced performance when the FI light is on. My reservation in doing that for a prolonged period would be if there was a situation where a genuine pre-ignition (pinging) problem had developed and went undetected by the rider. In this scenario, the ECM is not correcting for the problem. If left for a prolonged period, is one running the risk of engine damage as a result?
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Do we know that? Maybe, to the contrary, when the light comes on, the ECU is in fact constantly correcting (retarding timing?) for a problem that doesn't exist, hence loss of performance and mpg? Who knows?

As you say, some have been riding with the light on for a while, some have for years now, and no reports of major adverse effects yet?
 
MidLife said:
Do we know that? Maybe, to the contrary, when the light comes on, the ECU is in fact constantly correcting (retarding timing?) for a problem that doesn't exist, hence loss of performance and mpg? Who knows?

As you say, some have been riding with the light on for a while, some have for years now, and no reports of major adverse effects yet?
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I have read that others are living with this fault sode, I remember one person ststing he just stays under 70mph.

With my experience, the light resets everytime the bike is turned off, but returns once the bike runs over 4500rpm for approximately 10 seconds. I have tested this in my garage, and once the light trips the rpm drops about 500, as the timing changed to compensate for the perceived knock.

However, if I pull the battery connection, it resets completely, and will not trip, even at 100mph for 30 seconds. Eventually my light returns, afetr more than 300 miles.
 
MidLife said:
Do we know that? Maybe, to the contrary, when the light comes on, the ECU is in fact constantly correcting (retarding timing?) for a problem that doesn't exist, hence loss of performance and mpg? Who knows?

As you say, some have been riding with the light on for a while, some have for years now, and no reports of major adverse effects yet?
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-No, I don't know it for sure. I know ECM's often will default to a pre-programmed setting for the control circuit exhibiting the fault. If there was an engine knock still present beyond that threshold, there would be no further compensation.
What is the likelihood of that scenario? Pretty small I am sure.
What is the risk of engine damage? Also pretty small I am sure.
Do you want to chance it? Your call.
 
Daniel said:
I have read that others are living with this fault sode, I remember one person ststing he just stays under 70mph.

With my experience, the light resets everytime the bike is turned off, but returns once the bike runs over 4500rpm for approximately 10 seconds. I have tested this in my garage, and once the light trips the rpm drops about 500, as the timing changed to compensate for the perceived knock.

However, if I pull the battery connection, it resets completely, and will not trip, even at 100mph for 30 seconds. Eventually my light returns, afetr more than 300 miles.
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So that seems like the ECM reverting to some sort of limp mode, but only when the engine is pushed; all other things being equal. I wonder if some of these bikes that have this happen might also have low compression readings or the valve timing has changed slightly due to wear, even if a new ECU resolves the issue, a new ECU may have been changed to compensate for an older engine.

I think all the 13s are 10.8:1 and I haven't read anything about compression readings or if they get bad at any point.
 
Turns out my dealer is going to replace the unit because of their mistake. However, I tracked down a place called Steve's Cycle and Salvage in GA. They just quoted me $450 with exchange. Their number is 229-386-8666.
 
For shits and giggles I just looked up the price for my '04 here in Canada,...............you sitting down?...................$1875

Even accounting for exchange rate.........................just WOW!
 
Rhubarbray said:
For shits and giggles I just looked up the price for my '04 here in Canada,...............you sitting down?...................$1875

Even accounting for exchange rate.........................just WOW!
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Is that quoted from the local dealer, or have you managed to find an online oem parts source here in Canada? Inquiring minds.....
 
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