Suspension Control Unit error 44 on 2015 ES

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Lowcountry Joe

Well-known member
Joined
May 25, 2008
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Location
Near Rock Hill, SC
I probably caused this issue. For the first time, I left my ignition key on yesterday in the garage and the battery ran down last night. So I likely did another stupid thing and charged the battery back up with my Schumacher charger with everything still connected.

Once the battery charger showed fully charged, I disconnected it. Measured the voltage at the battery terminals and it was around 13.5 volts. So the battery was good to go now and I started the bike. It started right up no problem, but with the lack of voltage during the night to hold up the menus, everything was back to default. No problem, just went through the menu to set stuff back the way it was.

I did notice that there was a new warning symbol in the display that I had not seen before. It was the suspension warning lamps.

Now with the bike off, turning on the switch, placing bike in neutral, I page through the menus to find the suspension settings. Here is where I found the problem error code 44 when I switched to the preload menu setting.

Went to the service manual and discovered this code 44 has to do with failure to read from an eprom. Apparently I have an eprom issue in the suspension control unit (scu). Maybe I created it by charging the battery with everything still connected to the battery, just don't know. (dumb move on my part regardless)

I've ridden the bike and it feels just like it did yesterday, but the suspension warning lights are worrysome and I cannot take this bike to EOM unless I can get this resolved. If the bike has a faulty SCU, then who knows what it might do unexpectedly.

I have since disconnected the neg terminal of the battery to remove voltage from the system for a time to see if the scu might start acting normally, but to no avail.

So anyway, this is a very disappointing issue for me and the timing is terrible since I was planning to attend EOM in Lewisburg. If anyone has experience with this issue, please advise. I sure would like to fix it asap. Thanks

 
Ken,

I read the thread on the Owners Forum you referenced. Seems the chap reset his and all was well, hope I can do the same. My problem, and i have a service manual, is how to "run" diagnostic code 84. I am assuming that I place the bike in the diag mode, choose SCU, and then what? Any help would be appreciated. Thanks

 
LOL, yep, we did send off a few PM's to each other, hence no real info on that thread.

I'll switch the desktop on and try and find the info I sent Tim.

From memory it's a bit of a bugger to reset the steppers.

If not I'll have to try and scan the page in that bloody awkward manual.

Be back soon.

 
1st, leaving the key on was dumb, but you know that. Shit happens. Dumping my bike twice at the same gas station, on the same day a few years ago, was also dumb. These bikes can't freak out every time one of us does something dumb.

2nd, I don't see any issue with the way you charged the battery. Probably way better for the battery than starting the bike and force feeding it. That Schumacher is a 1.5 amp charge which is what you want. Leaving it connected should have no effect.

3rd, something's fishy with that SCU error. Even if the battery went fully dead, that shouldn't matter. What happens to the guys that take their batteries out for the winter, or even when you replace the battery? Losing power and then getting power forces the SCU into an error that is a PITA to clear? That's not good!

As far as worrying about your suspension, I wouldn't. If you can clear it before you leave, that'll be awesome, but expect it to happen again one of these days. If you can't, just take it and ride it. Even if it freaks out, it will just default to the factory settings. It's not going to buck you off or explode. Take a picture of the error light and email that to yourself. That way, next time it happens, you have a time stamp for the first occurrence and hopefully the mileage. My bet is this will end up being a warranty issue; Yamaha electrical systems being what they are.

 
I am pretty sure that this is the best knowhow fjr forum around the world...
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I'm still failing to see the advantage of ES. Glad you got it reset without a huge problem.
I've put ~5000 miles on two rental bikes that had ES. I found reasons to use it, me likie a lot and want it on my next bike. Back in the 70's when car cruise controls were rare I put Audovox cruise controls (!) in a couple of cars because I like it and use it. Every car there after had cruise and I like it. A lot of people have cars with cruise and never, ever use it, find it pointless, useless and an unwanted complexity. Choices are good because for sure we aren't all alike :)

 
Zilla...wanted to comment on a couple of your comments...

1st, leaving the key on was dumb, but you know that. Shit happens. Dumping my bike twice at the same gas station, on the same day a few years ago, was also dumb. These bikes can't freak out every time one of us does something dumb.
Yep, I was just reading the other day where one of our members left his key on and his battery ran down. I thought that would never happen to me because it has never happened before....but I was distracted when I dismounted the bike and I always kill the bike with the kill switch...so there you go...dumbarse me....dismounted the bike and never gave the key a second thought.

2nd, I don't see any issue with the way you charged the battery. Probably way better for the battery than starting the bike and force feeding it. That Schumacher is a 1.5 amp charge which is what you want. Leaving it connected should have no effect.

I was actually using my bigger Schumacher charger that I use for marine batteries. It's a great microprocessor controlled charger, but it's a lot more powerful than my Schumacher battery maintainers I use. One thing I did when the charger was connected to the battery was turn on the switch momentarily. That alone may have caused the glitch...who knows.
3rd, something's fishy with that SCU error. Even if the battery went fully dead, that shouldn't matter. What happens to the guys that take their batteries out for the winter, or even when you replace the battery? Losing power and then getting power forces the SCU into an error that is a PITA to clear? That's not good!
Again I believe it was my fault one way or another. In the past with this bike, I have disconnected the negative terminal many times when adding crap to the bike. So up to this point, I had never had an issue with the SCU when removing battery power from the bike. I believe it was my fault when I turned on the ignition with a dead battery and an unfiltered battery charger. Freshman move on my part.
Thanks for your thoughts.

 
Strewth, just when I found the procedure, lol lol. Had it on Google DocsGood news !!!
Ken...thanks a pile for making the effort to get me that info. It was your reply to my problem that ultimately pointed me in the right direction. I went over to Owners Forum and found the post about the 2014ES that had the same problem. Then, after reading that a couple of times, I dove back into the service manual. Occasionally, I find the service manual is a little difficult to follow. When it said to "run diagnostic 84" (if I was seeing error code 44) it didn't go into much detail as to how to actually "run diagnostic 84". But a little more research on different pages in the manual pulled together the sequence of button pushes to accomplish the deed.

I sincerely believe that it was my fault that the suspension warning lights and error code 44 popped-up due to either: my charger was not compatible, spark when connecting the charger to the battery (dumb me, always have charger unplugged when connected to your battery to prevent spark), or my uncontrollable urge to turn on the switch while the battery charger was still connected.

What I should have done when I discovered the dead battery due to my brainless act of leaving the switch in the "on" position over night:

-Repeat "I am a dumb butt" as many times as it takes to sink-in

-Disconnect the negative lead from the neg terminal of the battery before connecting charger

-Connect the charger to the battery before plugging in the charger

-Don't turn on the switch just to "see" if the battery is charging

-Review all menus for normality after the charging session is complete and charger is disconnected

There are a lot of electronics on these new bikes, so I suppose every now and then an electron or two will go the wrong way. The service manual was again worth every penny of it's $75 price from my dealer!

Thanks again!

 
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Great info and outcome.

Am I understanding that you eventually used a charger of greater than 2 amps on a bike battery. Everything I've been taught was that can cause problems even with "smarts" in the charger.

Has this changed?

 
More than likely the cause of the error was the voltage sensing to the SCU dropped below a threshold. I haven't looked at the construction of the SCU, but pretty sure there are capacitors that will maintain the voltage to retain settings long enough to change a battery. Because the key was on overnight it discharged the battery and any caps in the system taking all voltages to near zero. The reset is probably all you needed.

I, for one, love the ES. I love the ability to quickly change my suspension settings whenever the type of riding or what I am riding on changes. Especially the pre-load on the front.

 
...Went to the service manual and discovered this code 44 has to do with failure to read from an eprom. Apparently I have an eprom issue in the suspension control unit (scu). Maybe I created it by charging the battery with everything still connected to the battery, just don't know. (dumb move on my part regardless)...
More than likely the cause of the error was the voltage sensing to the SCU dropped below a threshold. I haven't looked at the construction of the SCU, but pretty sure there are capacitors that will maintain the voltage to retain settings long enough to change a battery. Because the key was on overnight it discharged the battery and any caps in the system taking all voltages to near zero. The reset is probably all you needed...
An EPROM and STATIC RAM are non-volatile = does not lose its memory when power is removed. Once the data or program is 'burned' into the device the only ways it can change is by ultraviolet light to erase it, electronically addressing the chip with new information or failure. When the motorcycle is powered up, an ECU will read some amount of information from the EPROM/STATIC RAM. If the charger caused electrical indigestion it is possible for the memory device to have been read incorrectly or corrupt a memory cell. The Engine Management ECU also has a fault code for failure to read data from an EPROM correctly.

When there are settings that you select which are supposed to be retained such as suspension selections and drive mode they are often stored in STATIC RAM. This is a device that works somewhat like an EPROM except it is intended to have data saved and changed frequently. The STATIC RAM can have the data corrupted more easily than an EPROM. When the STATIC RAM is reset, the default settings would be read from an EPROM. It is almost certain that the settings memory device had the memory scrambled or deleted and Low Joe just restored the defaults via the diagnostic screen.

DISCLAIMER: Note to the the correction and information completion police,this is intended to be a simple concept overview and not a complete and comprehensive engineering dissertation on memory devices or memory saving schemes. Yes, I left out devices such as EEPROMs and indeed, changeable data can be saved in a non ultraviolet EPROM. It is also possible that the EPROM or STATIC RAM is part of one DSP or computer chip and not a discrete component..

 
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I, for one, love the ES. I love the ability to quickly change my suspension settings whenever the type of riding or what I am riding on changes. Especially the pre-load on the front.
I don't think the ES can change the pre-load on the forks, just the damping.

 
Purely for accuracy:

...An EPROM and STATIC RAM are non-volatile = does not lose its memory when power is removed.

...
EPROM is non-volatile, EEPROM is non-volatile, FLASH memory is non-volatile.
STATIC RAM is volatile, it loses its memory when power is turned off. STATIC refers to it not needing to be refreshed, whereas DYNAMIC RAM does need refreshing (read and re-written at frequent intervals).

 
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