[aaron_]

So I have a 2010 N55 dct e93 335i with 100000kms. All maintenance including dct fluid flush (90000km) has been done. At 90000km the dct seals were also checked over and given the all clear.

Up until now car has been driving great. Today I drove 40km, then 5km, then 15 km, then 25km, all perfect. Went to start the car again and it wouldn’t start; many errors about start assistance inactive and transmission failure. The yellow P light on the dct shifter doesn’t illuminate and the car won’t start.

I left the car there for 5hrs, went back to it just now and it didn’t start. Reset codes, didn’t start. Reflashed my custom mhd tune and it started again. Moved it 10m, switched the car off to go say hi to my sister, then it didn’t start again but this time I’d blocked her driveway off. Reflashed the tune again and got it going again. Moved the car to a spot with front and rear tow truck access.

See the pics for error codes







EDIT:One thing I should add first is I had the roof down when the car was parked for 45mins and the sun was beaming in (round 4:45-5:30pm). I also flick the shifter across into sports mode and back to D (sports button always pressed) regularly.









Any ideas?

[Aus335iguy]

Firstly, don't panic. Although it's a complex machine and it looks bad it's most likely a module or wiring issue. I say that because of the intermittent nature of the fault but It could also be something as simple as a flat battery. Generally if something mechanical breaks it stays broken.
The fact you had work done recently on the DCT means there's a higher likely hood the repairer hadn't seated a plug correctly or damaged some wiring.

Start with some questions ..
Have you done any work recently in and around the shifter ?
What work have you done recently to the car?
Have you had a look at all the connections? going to the DCT ?
Can you take apart the centre console and check/ re seat all plugs going to the shifter unit ?
How old is your battery?
Do you have access to spare parts ?
Is there a decent independent repairer nearby?

[aaron_]

Originally Posted by Aus335iguy

Firstly, don't panic. Although it's a complex machine and it looks bad it's most likely a module or wiring issue. I say that because of the intermittent nature of the fault but It could also be something as simple as a flat battery. Generally if something mechanical breaks it stays broken.
The fact you had work done recently on the DCT means there's a higher likely hood the repairer hadn't seated a plug correctly or damaged some wiring.

Start with some questions ..
Have you done any work recently in and around the shifter ?
What work have you done recently to the car?
Have you had a look at all the connections? going to the DCT ?
Can you take apart the centre console and check/ re seat all plugs going to the shifter unit ?
How old is your battery?
Do you have access to spare parts ?
Is there a decent independent repairer nearby?

One thing I should add first is I had the roof down when the car was parked for 45mins and the sun was beaming in (round 4:45-5:30pm). I also flick the shifter across into sports mode and back to D (sports button always pressed) regularly.



I agree with module or wiring

With Work recently to the dct it was 10000km ago. That’s along time for something to happen after with no signs of driving issues or oil leaks.

As for your questions

No work recently
No I haven’t. I have no idea how to check that stuff
I’m going to YouTube and try
Battery is <6 months old and was registered correctly.
Spare parts = fcp or ecs
Yes for a good indy

[EB89]

Damn, I hate these ones.

Try to get a charger on the battery over night just to rule the battery out.

Reflashing MHD allows it to start once, that’s super odd, maybe try to fully remove and re write the 40min flash down?

[juld0zer]

I had a cruise contol failure after installing and coding a donor used DSC module. The fault was missing message between DSC and DME. I followed all the usual troubleshooting like swapping back my known good DSC control unit, another known good one, and even ran a new wire from the DSC to DME for the road speed signal.

Do you have Inpa?
Have a read of this thread: http://www.1addicts.com/forums/showt...1138536&page=2
The fix might be simpler than you think - you may just have to remind the DME that your car has a DCT.

[aaron_]

Turned out to be transmission control unit. $2700 later, fixed :-(

[EB89]

Originally Posted by aaron_

Turned out to be transmission control unit. $2700 later, fixed :-(

:O

[Aus335iguy]

Originally Posted by aaron_

Turned out to be transmission control unit. $2700 later, fixed :-(

Far out... did you keep the old one ?

[juld0zer]

😭😭

[EB89]

Man that’s so bad, that’s like my horror story.

Did a dealer get the part and do the install?

[Socket]

Crap. On the upside it’s running again

[Hoper]

That sucks Aaron, at least its fixed, fingers crossed that its reliable for a while now bud

[aaron_]

Went to pick the car up, did the exact same thing. Only difference is I’m poorer!!

It’s at a reputable specialist indy.

Any ideas guys ?

[woosh]

So you just paid $2,700 for .... ? Damn

[Aus335iguy]

That means that the fix isn't as dramatic as you think it is.
I would check/borrow a GWS unit and see if that does the trick. The TCU can always be sold to some poor soul who actually needs it.

I'm happy to try your GWS in my car to see if that's the issue. I'm time poor at the moment so you'd need to come to me. Sydney. North shore ...

[EB89]

Originally Posted by aaron_

Went to pick the car up, did the exact same thing. Only difference is I’m poorer!!

It’s at a reputable specialist indy.

Any ideas guys ?

Get a refund, wtf

I would take it to BMW

[e36mmm]

1. Take car back to shop
2. See if they can rectify issue without any further costs as they can expand list of parts to change to make more money evidently resulting in paying more. Do not fall for this.
3. Do not take car back until they fix it or demand money back and tow it to someone else that can fix it.
Keep us posted

[e36mmm]

1. Take car back to shop
2. See if they can rectify issue without any further costs as they can expand list of parts to change to make more money off you. Do not fall for this.
3. Do not take car back until they fix it or demand money back and tow it to someone else that can fix it.
Keep us posted mate

[aaron_]

When I went to pick the car up, it happened immediately. Never actually got it. Car was left there. In a hire car arrange through them now. Returned my no birds corolla.

As I said, they’re reputable, just a tricky problem.

[aaron_]

Originally Posted by Aus335iguy

That means that the fix isn't as dramatic as you think it is.
I would check/borrow a GWS unit and see if that does the trick. The TCU can always be sold to some poor soul who actually needs it.

I'm happy to try your GWS in my car to see if that's the issue. I'm time poor at the moment so you'd need to come to me. Sydney. North shore ...

GWS = ?


Will speak to them tomorrow and get in touch if it would be beneficial. Appreciate the offer

[Aus335iguy]

The module in the centre console that does the shifting. I'll bet money there's a cable loose or pinched/damaged from when you've had work done previously. What year is your car ? N54 or n55

[e36mmm]

^ That could highly be the cause of the problem. Good tip. Im curious now to see what the problem is..