Jester99

Hello!

My first post here - I've been reading the forum for just under a year and found a lot of useful information. There are some very knowledgeable posters on this board.

I have a 2005 645ci which I have had for about five months and I have a question regarding the braking: if I?m in slow moving traffic and I take my foot off the brake the car will creep forward as its an auto but when I re-apply the brake I just can not bring the car to a smooth stop. Its starts to slow down and then it?s as if I?ve pressed the brake pedal much harder and the car suddenly stops. It?s not just in slow moving traffic; the same can happen as I slow down to approach a junction and it does this all the time. It doesn?t matter if the discs are cold or hot either.

It?s been back to the dealer about five times for various other issues (don?t ask) and each time they tell me the brakes are fine and exactly the same thing happens on any other 645. I?m sure this isn?t true as I would have noticed it on the numerous test drives I took.

Does anyone else here have the same issue or am I just unlucky?

I do have a bunch of other issues with it but I can just about live with them. It?s the braking that?s really annoying.

Thanks for any help you may be able to offer.

m630

welcome

i cant say i have this issue as i drive mostly in manual mode and downshift to slow down and dont rely too much on brakes; however, perhaps your tranny is part of the issue, when was the last software update you had? many of these things are software controlled now and that may be contributing

Jester99

Thanks for the welcome.

The last software update was around December 2006 I think. I'm assuming they updated the software as some of the icons in the Nav screen have changed. I took the car in to have an issue with the PDC sensors and an issue with the iDrive locking sorted out and I think they resolved it by updating the software. I believe you can't tell which version of the software you have without asking the dealer so I can't say what version I'm on now, sorry.

Doc Horror

Sorry to hear about your problem(s).
Can't say I have this problem. But I have an automatic.

cobradav

I have heard of this although I have not experienced it in 39k miles. Like m630, I use the manual mode of STEP alot and so not on the brakes alot as as evidenced by my more than 50% left on brakes. The few complaints I saw were from 650s and we thought it was something unique to them.

zen

Might have some air in the lines so that on the first application you are compressing air and on the second you are pushing on the fluid (which is not compressable).

diveleader

I have a similar problem on my E60 - as you stated, its difficult to come to a smooth stop.
I got the dealer to reprogram or update the gearbox computer and this has made it a bit better, although its still there.
could it be the large brake discs?

diveleader

I have a similar problem on my E60 - as you stated, its difficult to come to a smooth stop.
I got the dealer to reprogram or update the gearbox computer and this has made it a bit better, although its still there.
could it be the large brake discs?

biggun

Funny i had the same problem, i took to my dealer, they updated the idrive (due to problems i was having), but their offical reply was "because the brakes are so large (520d?!?) it will jolt the car".

But i was under the impression that 'soft stop' technology was meant to prevent it?