DQS not working on downshifts

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This is all about making the auto blipper work appropriately. Upshifts work even when your downshifter doesn't. There's logic being applied to the blipper and when parameters are out of range it won't blip. So when it can't blip no downshift. I'd change technicians or if this is a Ducati dealer call the factory rep.
 
I don’t “think it’s just sensor values.” I don’t know what I wrote to give you that idea. My experience goes quite to the contrary as evidenced clearly in this thread.

Please stop pretending to be an expert.
 
Since you are obviously the expert why don't you help this guy fix his bike. Some of us have a lot of experience with computer controlled devices. This is a safety issue for Ducati. If the system would allow a downshift without a blip you could lock the rear up (ever used a bidirectional quickshifter without an autoblipper). If the other systems can't catch this then you would create parameters to insure this never happens. That's why these don't work when you make seemingly small changes. They need to be within the defined ranges to work. Period. It has to fail safe. Again the issue here is lack of diagnostics (no thrown codes). Since this seems to be a warranty issue if I were Ducati I'd add onboard diagnostics because in the end it will be cheaper to do so. You have a guy at a dealer who is incapable of fixing this. If this bike's driveline is stock and they can't fix it I'd invoke the lemon law.
 
Tech will be installing a new gear position switch , said they've seen that be an issue before, which makes more sense to me as the blipper works perfect in lower gears. If the bike isn't clear on what gear its in it won't know what timing & dwell to apply for a downshift (in theory, anyways, as is eveything in discussion here).
If that doesn't resolve then I will return it to the original final drive ratio and see what that brings. We aren't sold on that being the core issue otherwise downshifts wouldn't work in any gear- final drive ratio is static, so differences in wheel speed to what the ECU expects is the same from 6-4 as 3-1 and it isn't changing its mind half the time.
Carefully following a step-by-step troubleshoot is a slow and deliberate process, unfortunately
 
I'm going to try this one more time. This is the sequence I used the first time to restore the downshifter. This would not work when I had 17/36 gearing. Then I think SFV4 or SuperD posted the allowed regearing for first the panigale then the SF. When I saw the SF list, I realized that my gearing was outside of what change was allowed so I dropped the front one tooth to 16/36. Then as the bulletin says I attempted a calibration (failed) and went in and cleared the adaptives. Both transmssion and DQS. Went for a ride and rode for awhile using the clutch then tried the DQS. Upshifts had improved (a suprising amount) but the sucker still won't downshift. Then I tried to recalibrate. It accepted the recalibration. The downshifter came back on. At that point the lite came on and I realized when you dump the transmission adaptives there's nothing in the register. The ECU wants to know the rearwheel speed accurately. When you change the gearset, say 10%, the change spread between the gears in road speed is also 10%. In order to blip appropriately the ECU wants to accurately know what the RPM needs to be at the completion of the downshift. So the initial calibration is allowing it to have a basis on which to do so. Once the first calibration is done the rpm versus rear wheelspeed is known for second gear (and since the ECU can also see what gear you're in it knows the wheelspeed vs RPM for all points). This number is stored (and It now becomes the basis for recalibration). To blip accurately the DQS wants to ensure that its stored parameters are within about (it appears) 3- 5%. This will allow for tire wear and slight variations between brands. The system is sampling to ensure that the rear wheelspeed agrees with the stored parameters. And if it doesn't agree within the allowed tolerance, no downshift. It also has to know what gear it's in and the expected values of the output of the switch on the shifter. The DQS also stores these values so when you change the switch you have to do a DQS adaptives reset. And as the user manual says the throttle needs to be completely closed. So if the TPS calibration is off this can also cause a failure. I also believe that to allow some tolerance here Ducati maps the optimum torque maps first point, which is 5%, to 0. If everything is OK it blips. Realize that this is the only system on the bike that other than you thru the ETV map in the ECU that is allowed to open the throttle. Every other system, DTC, DWC, DSC modulates by closing the throttle. Oops GP's on. Hope this helps.
 
baggerman said:
I'm going to try this one more time. This is the sequence I used the first time to restore the downshifter. This would not work when I had 17/36 gearing. Then I think SFV4 or SuperD posted the allowed regearing for first the panigale then the SF. When I saw the SF list, I realized that my gearing was outside of what change was allowed so I dropped the front one tooth to 16/36. Then as the bulletin says I attempted a calibration (failed) and went in and cleared the adaptives. Both transmssion and DQS. Went for a ride and rode for awhile using the clutch then tried the DQS. Upshifts had improved (a suprising amount) but the sucker still won't downshift. Then I tried to recalibrate. It accepted the recalibration. The downshifter came back on. At that point the lite came on and I realized when you dump the transmission adaptives there's nothing in the register. The ECU wants to know the rearwheel speed accurately. When you change the gearset, say 10%, the change spread between the gears in road speed is also 10%. In order to blip appropriately the ECU wants to accurately know what the RPM needs to be at the completion of the downshift. So the initial calibration is allowing it to have a basis on which to do so. Once the first calibration is done the rpm versus rear wheelspeed is known for second gear (and since the ECU can also see what gear you're in it knows the wheelspeed vs RPM for all points). This number is stored (and It now becomes the basis for recalibration). To blip accurately the DQS wants to ensure that its stored parameters are within about (it appears) 3- 5%. This will allow for tire wear and slight variations between brands. The system is sampling to ensure that the rear wheelspeed agrees with the stored parameters. And if it doesn't agree within the allowed tolerance, no downshift. It also has to know what gear it's in and the expected values of the output of the switch on the shifter. The DQS also stores these values so when you change the switch you have to do a DQS adaptives reset. And as the user manual says the throttle needs to be completely closed. So if the TPS calibration is off this can also cause a failure. I also believe that to allow some tolerance here Ducati maps the optimum torque maps first point, which is 5%, to 0. If everything is OK it blips. Realize that this is the only system on the bike that other than you thru the ETV map in the ECU that is allowed to open the throttle. Every other system, DTC, DWC, DSC modulates by closing the throttle. Oops GP's on. Hope this helps.
Click to expand...

Catching up on the race myself..
So in your case, did the issue appear pretty much immediately after the gear change? And did it only affect upper gears as mine is now? I will be following all steps you laid out here for sure, however if this ends up being the cure it will be baffling to me as the bike's had the same gearing for over 2 years yet the QS starting trying to kill me only recently.
Appreciate the detail in explanation, this is what I go to these forums for.
 
bp_SFV4 said:
Take software courses. Or if you have a friend who codes ask him to explain how control software works.
skidrumr said:
Catching up on the race myself..
So in your case, did the issue appear pretty much immediately after the gear change? And did it only affect upper gears as mine is now? I will be following all steps you laid out here for sure, however if this ends up being the cure it will be baffling to me as the bike's had the same gearing for over 2 years yet the QS starting trying to kill me only recently.
Appreciate the detail in explanation, this is what I go to these forums for.t from changing gearing. If a previously stored value becomes invalid due to sensor drift or failure
Click to expand...

Immediately upon a gearing change. But I made a big change. The system seems to tolerate a change of a tooth or two on the gearing (it'll still recalibrate). If a sensor value is stored and then the value drifts or the sensor fails, no shifter. Thats why the suggestion to reset everything.
Click to expand...
 
You seem to be having some trouble with the quote tool and attributed your reply as if it were something I wrote.

I also take it by your response you are unable to post information about this "register" which you wrote about as if you had firsthand knowledge of same. You are writing about ECU workings as if you have some higher level firsthand knowledge. You don't. You are merely making observations and guessing but then you come here and write about it as if you are an expert.

All conjecture.
 
It would be useful if you read about how air/fuel adapatives work (O2 sensors). Not the physics of the sensors but how the software works. Should be readily available on the internet somewhere. Should help allay your ignorance. If that doesn't help take an intro software class at a JC. Then come back and tell me how wrong I am. Good luck.
 
kkK.gif
 
More nonsense and BS. Thanks for the contribution. They should make you a certified Ducati master tech with all your guess work.

Why don’t you guess how many ..... I give about your opinion?
 
Props @baggerman, the switch back to stock gearing did the trick. The fact that this isn't the immediate 1st question by the dealership or service technician is staggering to me, and Ducati would do all of their owners a favor by letting us know what the programming will tolerate. I'm guessing the percentage of owners keeping these bikes bone stock is very small.
I did a bunch of calculations around the 5% variation: stock gearing is 15/42 or 2.8:1, and I had gone to 14/43 which is 3.07:1 or more than 8% change. Bike ran like a striped ape until it decided not to anymore. I'm wondering if running a 200/55 slick at track days was the last straw. The fresh set is 200/60 so that won't be part of the equation now.
My goal is still to get the shortest possible ratio, but if it has to fall into that 5% range- that would have to be 15/44 which is 2.933:1 or 4.54% change.
14/42 is close at 3.0:1 but still a 6.66% change (the devil's percentage, apparently); it's worth the try as I have both those sprockets on hand already and can quickly revert.

What I don't have an answer to is why the issue was simmering slowly and not an immediate problem, because that is a much easier troubleshoot.
I'll be glad to have the beast back, just bummed I lost a whole riding season chasing this
 
skidrumr said:
Props @baggerman, the switch back to stock gearing did the trick. The fact that this isn't the immediate 1st question by the dealership or service technician is staggering to me, and Ducati would do all of their owners a favor by letting us know what the programming will tolerate. I'm guessing the percentage of owners keeping these bikes bone stock is very small.
I did a bunch of calculations around the 5% variation: stock gearing is 15/42 or 2.8:1, and I had gone to 14/43 which is 3.07:1 or more than 8% change. Bike ran like a striped ape until it decided not to anymore. I'm wondering if running a 200/55 slick at track days was the last straw. The fresh set is 200/60 so that won't be part of the equation now.
My goal is still to get the shortest possible ratio, but if it has to fall into that 5% range- that would have to be 15/44 which is 2.933:1 or 4.54% change.
14/42 is close at 3.0:1 but still a 6.66% change (the devil's percentage, apparently); it's worth the try as I have both those sprockets on hand already and can quickly revert.

What I don't have an answer to is why the issue was simmering slowly and not an immediate problem, because that is a much easier troubleshoot.
I'll be glad to have the beast back, just bummed I lost a whole riding season chasing this
Click to expand...

I haven’t read all the posts, if you still have an issue it could be same as I had. The gear position sensor was getting to hot and one failed completely and another was intermittent. The total failure would change up or down ECU went nuts and the motor would misfire all on track , admittedly hot conditions. I now have fitted a cooling duct to the sensor… fixed
 

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