DCT failure - gear indicator flashing, and can only jump between Neutral and 2nd (kinda)

[tvu]

Hi guys. I'm hoping you guys can help me diagnose what may be going on. I'm having an issue where the gear indicator is blinking "-" and cannot engage the transmission. In the video below, as I start the bike, it shifts back to "N" from "2". Once I start my bike, I can set it to "D" but it will jump straight to 2nd gear (you can hear in video). The indicator continues to flash at "2" but I cannot down shift, up shift, to go manual, or take the bike back to Neutral while the engine is running. The only way I can bring it back to neutral is to turn off the engine while in 2nd, and let the gear motor take it to "N" when I initially turn the bike on.

I have confirmed it is not battery issue. My OC voltage is 13.0V on a brand new Yasua YTZ14S. Charging voltage is 14.5 while the engine is running. I have disconnected all accessories in case those were the culprit but they are not.
This first happened to be about 2 months ago (~500 miles ago), but after turning the engine on/off a few times I was able to resume as normal. This time around, I've been struggling for a week, replace battery, etc etc but no dice.

Bike is 2015 NC700XD. 9k miles. Had full 8k service done at an authorized dealer.

Any thoughts?

Here's a video. Walking through it:
1) When I first start the bike up, it clicks 3 times and takes the bike from 2nd to Neutral (indicator still blinking "-")
2) When I put it in "D" it jumps straight from Neutral to "2" (indicator blinking "2")
3) Once I'm in 2nd gear, I cannot up shift, down shift, return to Neutral, or activate manual mode (+/-) or M/T.
4) I can turn the bike off while in 2nd gear
5) If I turn bike back on, go back to step 1 above.

New video by Tien Toan Vu

photos.app.goo.gl

 

[mzflorida]

Sorry to hear it. If you are able, and only after you have warmed up the bike, try this (if you are able).

• Start the engine.
• Select N
• Stop the engine.
• While pressing D, switch the ignition on, wait until the yellow ‘engine' symbol goes out on the dash, then release D
• Press in fast sequence: DDNDN
• On the dash, the letters D and S should appear together
• Restart engine, allow it to idle.
• After a few seconds, the letters D and S should go out.

Another step would be to rock the bike while it is in gear.

I'm unsure if the NC has a ECM soft reset function.

 

[lootzyan]

First of all, your bike's power-on is modified which you didn't mention. At the beginning, we see that the combination meter has power, but the initial test before start is only initiated when you do something out of view.
In the seventh second of your video, I hear a rather unfamiliar sound. And from the very beginning the gear display is blinking, which means that there is a fault in DCT.
Have you tried rolling the bike forward and backward? If this does not help, diagnostics in a shop is rather required.

 

[tvu]

First of all, your bike's power-on is modified which you didn't mention. At the beginning, we see that the combination meter has power, but the initial test before start is only initiated when you do something out of view.
In the seventh second of your video, I hear a rather unfamiliar sound. And from the very beginning the gear display is blinking, which means that there is a fault in DCT.
Have you tried rolling the bike forward and backward? If this does not help, diagnostics in a shop is rather required.

I'm not sure what bike's "power-on is modified" mean. My recording sequence begins after I have put the bike in 2nd gear and cannot get back to neutral. When I first start the bike, the kill switch is engaged, when I disable the kill switch, the bike goes to neutral.

 

[tvu]

Sorry to hear it. If you are able, and only after you have warmed up the bike, try this (if you are able).

• Start the engine.
• Select N
• Stop the engine.
• While pressing D, switch the ignition on, wait until the yellow ‘engine' symbol goes out on the dash, then release D
• Press in fast sequence: DDNDN
• On the dash, the letters D and S should appear together
• Restart engine, allow it to idle.
• After a few seconds, the letters D and S should go out.

Another step would be to rock the bike while it is in gear.

I'm unsure if the NC has a ECM soft reset function.

Unfortunately I'm unable to do a DCT reset. DDNDN step does not bring up the DS on the dash. I think it's tied to the fault of flashing gear indicator.

 

[670cc]

Unfortunately I'm unable to do a DCT reset. DDNDN step does not bring up the DS on the dash. I think it's tied to the fault of flashing gear indicator.

Don’t worry about it much. The procedure referred to here as a “DCT reset” is a clutch characterization routine primarily meant to be used at clutch replacement. I doubt it has much to do with your transmission failure.

I can’t diagnose your specific transmission failure based on evidence so far, but in general it seems like the shift motor is lately the most often seen defective DCT component here on the forum. Problems have been resolved by replacement or cleaning of the shift motor, although the problem typically affects higher mileage bikes than yours. I don’t own a DCT, but if I did, based on what I’ve read, I would do proactive maintenance on the shift motor because of it’s high failure rate. I suggest if you are handy enough, to disassemble and internally clean the shift motor. It may not solve your problem, but couldn’t hurt it either.

 

[lootzyan]

...When I first start the bike, the kill switch is engaged, when I disable the kill switch, the bike goes to neutral.

Ok, this explains what is seen in the first seconds of your video: power on with kill switch on "no-run". But that doesn't make much sense. Normally you should forget about the existence of a kill switch. Federal requirements for kill switch functionality are quite different from what many people do with it.
I would advise you to start your diagnosis as recommended in the owner's manual and service manual. The recommended process makes sense because it is sequential. You avoid guessing what to do next.
Normally, if the DCT is not in neutral, the PCM should not allow the engine to start. It allows you to start in exceptional cases, with the brake on.

 

[tvu]

Ok, this explains what is seen in the first seconds of your video: power on with kill switch on "no-run". But that doesn't make much sense. Normally you should forget about the existence of a kill switch. Federal requirements for kill switch functionality are quite different from what many people do with it.
I would advise you to start your diagnosis as recommended in the owner's manual and service manual. The recommended process makes sense because it is sequential. You avoid guessing what to do next.
Normally, if the DCT is not in neutral, the PCM should not allow the engine to start. It allows you to start in exceptional cases, with the brake on.

Thanks. Pretty much everything in the manual points me to a dealer since it's transmission related. Fingers crossed at this point it's something fairly easy to find and fix and them not taking a shotgun approach.

 

[the Ferret]

I don't know, but a lot of issues I've read about on here with the DCT seem to be related to guys using their emergency kill switch for stopping the engine rather than the key.

 

[Zalm]

... using emergency kill switch for stopping the engine...

and battery voltage drops, drops (especially with bulb 55w ?), until thinking about cutting the key. See a voltmeter...

 

[Griff]

Completely unrelated to the above specific issues but I came across this comment from an inmate over on the Strom forum. Perhaps the folks in the know on here could let me have their comments for onward transmission.......

"Word of warning about the Honda DCT. It's good BUT - it's not serviceable, once the clutch packs inside go you have a paperweight not a bike."

 

[670cc]

Completely unrelated to the above specific issues but I came across this comment from an inmate over on the Strom forum. Perhaps the folks in the know on here could let me have their comments for onward transmission.......

"Word of warning about the Honda DCT. It's good BUT - it's not serviceable, once the clutch packs inside go you have a paperweight not a bike."

Word of warning about the internet: there is misinformation everywhere.

Those quoted comments are complete nonsense. The transmission is totally serviceable just as a manual transmission would be. Granted, you likely can’t repair, only replace, the computer, but all mechanical parts are serviceable.

Ask that person to show the DCT section of the Honda service manual that describes servicing the DCT, and how they somehow determined instead that it’s not serviceable.

 

[dduelin]

Completely unrelated to the above specific issues but I came across this comment from an inmate over on the Strom forum. Perhaps the folks in the know on here could let me have their comments for onward transmission.......

"Word of warning about the Honda DCT. It's good BUT - it's not serviceable, once the clutch packs inside go you have a paperweight not a bike."

That's just uniformed and completely wrong. He must be thinking of the Suzuki Burgman 650's computer controlled CVT transmission. According to the service manual a clutch pack replacement is a simple unbolt the old one and bolt in the new one. All the separate DCT clutch and transmission components are available from Honda for replacement if required..... but who has ever had to replace one or both clutch packs? With the PCM computer controlling clutch operation it's never abused by the rider and always engages and disengages in a narrow range of operation to ensure long service life. A few manual owners have reported having to replace clutches in manual transmission bikes but we've not heard of anyone doing so in a DCT bike. Not saying it hasn't happened, it's just extremely uncommon to this forum.

 

[lootzyan]

...Those quoted comments are complete nonsense....

Completely accurate.
Tell this "inmate" - "Read books and it might be good for you."
In the case of, for example, a clutch kit replacement in DCT, it is well described in our "Good Book". Besides, I do not remember that anyone on this forum mentions the replacement of the clutch kit himself, which may be a good sign of the durability of the clutch in DCT.

 

[Griff]

Thanks for the responses folks. I have enlightened the errant Strom inmate