Shifting issues

[tranquility]

Have DCT and this happened twice so far (mind you in 6 yrs of driving) when I press the gas aggressively from a stop, even though I'm in D reg mode, it somehow switches to M1 and gets stuck in 1st until I shift. The shifter was not pushed to the side and remained straight.

Obviously, a software prb but wondering if anyone has any exp?

[t612]

Had a 2011 Z4 35i and now a 2016 Z4 35is. Have not experienced what you described on the DCT.

[jts1981]

Originally Posted by tranquility

Have DCT and this happened twice so far (mind you in 6 yrs of driving) when I press the gas aggressively from a stop, even though I'm in D reg mode, it somehow switches to M1 and gets stuck in 1st until I shift. The shifter was not pushed to the side and remained straight.

Obviously, a software prb but wondering if anyone has any exp?

Maybe has something to do with the kick down switch? Did you press the pedal all the way down?

[tranquility]

Originally Posted by jts1981

Maybe has something to do with the kick down switch? Did you press the pedal all the way down?

Does the switch literally have to be floored to activate? I don't think that I touched the floor but I definitely pressed a big range on the pedal since I wanted to accelerate fast off the line.

[jts1981]

Originally Posted by tranquility

Does the switch literally have to be floored to activate? I don't think that I touched the floor but I definitely pressed a big range on the pedal since I wanted to accelerate fast off the line.

Yes. If you put your foot all the way down you should feel it click. You wouldn't notice it unless you know it was there. It pretty much will downshift gears to get you in the proper rev range. You may have been hitting it accidentally.

[tranquility]

Originally Posted by jts1981

Yes. If you put your foot all the way down you should feel it click. You wouldn't notice it unless you know it was there. It pretty much will downshift gears to get you in the proper rev range. You may have been hitting it accidentally.

Still, even assuming I hit the switch, it shouldn't be *M*1, right? Rather, it should still remain in *D* and upshift automatically. What happened is that the computer thought I was in manual mode when I'm clearly just in reg D mode.

[35i-Nut]

I have DCT , It should remain in D under those circumstances

Has it done it again ?

[tranquility]

Originally Posted by 35i-Nut

I have DCT , It should remain in D under those circumstances

Has it done it again ?

2 times over the span of 6 years...maybe it's a freak occurrence? Kinda like those 'dancing windows'?

[35i-Nut]

I wouldnt worry about it unless it becomes more frequent , enjoy the car try not to worry

[BQTuning]

There is a strong possibility the OP is on an older software, and depending if its a EU or NA released car may have something to do with it as the logic maybe different.

If you have a DCT Z4 it is highly recommended to keep up to date with the latest BMW software which also has updates for your DCT.

[tranquility]

Originally Posted by ********

There is a strong possibility the OP is on an older software, and depending if its a EU or NA released car may have something to do with it as the logic maybe different.

If you have a DCT Z4 it is highly recommended to keep up to date with the latest BMW software which also has updates for your DCT.

Is this free by the dealership regardless of warranty? Not sure what you meant re EU/NA?

[BQTuning]

Originally Posted by tranquility

Is this free by the dealership regardless of warranty? Not sure what you meant re EU/NA?

Well if you car is still under warranty or CPO it will cover it. If not, then you will have to pay like $250 - $350 USD depending on how nice the service rep is.

EU = Europe
NA = North America

Best advice is not to treat this car like a Automatic, you don't have a torque converter. It's more closer to a manual transmission. Your triggering the transmission safety to protect itself.

If you want to get aggressive with the car go into manual mode with Sport button on to avoid clutch slippage.

You might want to read this post

http://www.e90post.com/forums/showthread.php?t=747010

[tranquility]

^Tx for the link. Are we talking about the same thing, though? I'm not experiencing clutch slip, just that it is stuck in 1st gear due to accelerating from a stop even though it should be in automatic (and not manual) mode and I'm expecting an upshift as it reaches the shift pt/rpm.

[robertd33]

just to make sure... are you accidentally touching the paddle shifter?
whether in M or D, that describes exactly what it would do.

[BQTuning]

Originally Posted by tranquility

^Tx for the link. Are we talking about the same thing, though? I'm not experiencing clutch slip, just that it is stuck in 1st gear due to accelerating from a stop even though it should be in automatic (and not manual) mode and I'm expecting an upshift as it reaches the shift pt/rpm.

You're not experiencing clutch slippage..... yet, you are experiencing a safety preventative, so it stops you from shifting till RPMs fall with in safe range or load safe range. If after RPMs fall and you still not able to shift then there is a overheat issue or simply the control valve is stuck (I doubt this is the cause).

On the link I provided if you go over the PDF it will let you know how your DCT works.

The operating pressure is determined by a regulated control valve depending on the load
and the function selected. The system is protected by a pressure relief valve in the pump.
The pressure is regulated according to the following priorities:
• Clutch engagement and disengagement
• Gear changes
• Cooling the clutch
• Lubrication cycle.
The transmission oil pressure should be high enough to:
• Be able to engage the clutches reliably.
• Allow the gear selector rod to reach the required control shift speed.

So you are experiencing is a pedal gear input that is not liked. The transmission control unit or the TCU references a load to torque table. Well obvious when you smash on the gas in an incorrect "function" ie D mode, sport off , you are requesting a load that the TCU determines as unsafe.

Now on the newer BMW software the transmission is updated to tolerate such driving input and will practically up shift the car.

[tranquility]

Originally Posted by robertd33

just to make sure... are you accidentally touching the paddle shifter?
whether in M or D, that describes exactly what it would do.

Nope, didn't touch the paddle or shifter.

Originally Posted by ********

You're not experiencing clutch slippage..... yet, you are experiencing a safety preventative, so it stops you from shifting till RPMs fall with in safe range or load safe range. If after RPMs fall and you still not able to shift then there is a overheat issue or simply the control valve is stuck (I doubt this is the cause).

On the link I provided if you go over the PDF it will let you know how your DCT works.



So you are experiencing is a pedal gear input that is not liked. The transmission control unit or the TCU references a load to torque table. Well obvious when you smash on the gas in an incorrect "function" ie D mode, sport off , you are requesting a load that the TCU determines as unsafe.

Now on the newer BMW software the transmission is updated to tolerate such driving input and will practically up shift the car.

Dude, you lost me, no idea what you're talking about. I don't get why I need a software upgrade: this is just a very basic ftn that exists from the beginning of software version 1. If I mash the pedal while in D, it should just aggressively shift up but still automatically do so (staying in D mode), not suddenly go into M mode and require me to manually upshift. I didn't put it into S or M mode, and didn't inadvertently touch the paddles/shifters, so it should remain in D mode, i.e. fully automatic mode and w/o the danger of it hitting the redline while staying in 1st gear. As such, there's nothing 'safety preventative' about this and in fact, quite the opposite as it risks redlining. It's most definitely a software error/prb, just wondering if others have exp'd it and what they did about it.

[BQTuning]

Originally Posted by tranquility

Nope, didn't touch the paddle or shifter.




Dude, you lost me, no idea what you're talking about. I don't get why I need a software upgrade: this is just a very basic ftn that exists from the beginning of software version 1. If I mash the pedal while in D, it should just aggressively shift up but still automatically do so (staying in D mode), not suddenly go into M mode and require me to manually upshift. I didn't put it into S or M mode, and didn't inadvertently touch the paddles/shifters, so it should remain in D mode, i.e. fully automatic mode and w/o the danger of it hitting the redline while staying in 1st gear. As such, there's nothing 'safety preventative' about this and in fact, quite the opposite as it risks redlining. It's most definitely a software error/prb, just wondering if others have exp'd it and what they did about it.

Ok apologies, we are looking at this from two different aspects.

[Tangent]

With it being twice in that time span I'd not worry about it. My E46 over the 10 years and 180,000 miles I drove it has done a few goofy things too. Once it started up and ran on what felt like 3 cylinders but shutting it down and restarting it fixed it. Twice the speedometer needle suddenly was super sluggish for about a minute before starting to respond normally. Our cars have a huge amount of electronics in them; it's not too surprising when it occasionally strokes out and does something it shouldn't.

[rking117]

Originally Posted by jts1981

Maybe has something to do with the kick down switch? Did you press the pedal all the way down?

I'm pretty sure the kickdown switch will not put the vehicle in M1. It might move it to S1 but M1 would be reserved to when you either move the gear shifter to the left and down/up shift or hit the paddles. Also in the event that you do accidentally hit the paddle if you are in D and not S1 then the drive will recover and move back to D without much fuss. You may hit the rev limiter before that happens if you keep your foot in the gas.

The issue you are describing sounds like a software glitch or hardware issue with either the paddles or the joystick itself. I still have my new shifter sitting on a shelf waiting to install because when i move my shifter left it does not switch to S1. A sensor went bad and yep you guessed it. You cant replace the sensor without replacing the whole shifter. 550.00USD is what i paid for a new one not sure what they are going for now.

[nwe5000]

So bought my 2015 BMW Z4 28i (msport package) about a year ago. Now i'm experiencing the same issue but in a much worst way. Sometimes when i start my car and engage in D mode, it starts in M1 and will not shift. Sometimes it starts in M2 and it starts shifting sporadically until it engages back to D mode (This keeps happening 2-3 times a week). Now, another issue i noticed with this, when we got the severe heat in VA, it kept starting in M1 mode not in D mode. I would have to turn off the car on and off 2-3 times before it engaged back in D mode. There's gotta be something wrong with wiring? The shifter itself? Software update? Im gonna take it into a BMW expert shop i found this week to see what he says about it. Did anyone find a fix to this specific problem yet?

[B21]

Originally Posted by nwe5000

So bought my 2015 BMW Z4 28i (msport package) about a year ago. Now i'm experiencing the same issue but in a much worst way. Sometimes when i start my car and engage in D mode, it starts in M1 and will not shift. Sometimes it starts in M2 and it starts shifting sporadically until it engages back to D mode (This keeps happening 2-3 times a week). Now, another issue i noticed with this, when we got the severe heat in VA, it kept starting in M1 mode not in D mode. I would have to turn off the car on and off 2-3 times before it engaged back in D mode. There's gotta be something wrong with wiring? The shifter itself? Software update? Im gonna take it into a BMW expert shop i found this week to see what he says about it. Did anyone find a fix to this specific problem yet?

The previous conversation related to the 7 speed Getrag DCT box..yours is the ZF8HP auto box..completely different..

How many miles?

Checked to fluid level?

[nwe5000]

Originally Posted by B21

The previous conversation related to the 7 speed Getrag DCT box..yours is the ZF8HP auto box..completely different..

How many miles?

Checked to fluid level?

My Z4 has 2.0 liter engine, 4 cylinder; 59,284 miles. Which fluids you want me to check? Thank you!