HI all,

You may recall my previous thread, regarding electrical probs...
http://forums.bimmerforums.com/forum/showthread.php?t=926779

Basically, one day I unlocked my E66, and the windows dropped and the sunroof opened. I started the car, and the mileage read 999999 on the odometer. Each time I took the key out of the ignition, the windows dropped, and sunroof opened.
I took the car to BMW dealer, and they charged me £200 to tell me they didn't know what the problem was. I made a bit of a fuss, and they told me they had 'fixed' the problem, by disconnecting the battery, and then reconnecting it.

On the way home from the dealers, my car reported "Drive system failure - Drive moderately".
Over the next few journeys, this message appeared intermittently.
Today, the car reported the same error, along with a bunch of others, relating to parking brake failure, and others which I cannot recall. Within seconds of these errors being reported, the errors cleared from the 'Check' section on Idrive - without even stopping or starting the engine.
I continued along my journey, and the car continued to intermittently report 'Drive system failure', and also the 'check engine' symbol on the dash would illuminate, and the engine would stutter - as though the ignition had cut out for under a second, and 'restarted'.
As I was doing around 70mph on a motorway (highway), the car was acting erratically, and appeared to have an electrical fault causing the ignition to cut-out, and then restart almost instantly. The engine symbol on the dash would also illuminate for a second or so, during this period.

Does anyone have any suggestions regarding a possible cause of the problem?
My battery is old, but still throws out 12.1v with the engine off. There is 14.8v in the system with the engine running.
The battery always starts the car, and I would have thought a suspect battery would have had trouble starting the car (??)

Someone suggested a possibly 'grounding / earthing' electrical problem..... How do I check / fix?

Could it be a software issue?

Any help at all appreciated.

Thanks

Another update on this one......

I found the battery terminals not tight, and tightened them up.
I went out in the car, and got around 10miles away from home, when I got the "Drive Control system failure - Drive moderately" error.

Within seconds the engine started to stutter again, and stall.
I pulled off the motorway, and attempted to turn around.

The car stuttered badly, and the engine was obviously being starved of electricity. The rev counter kept dropping, and the dials were resetting (showing the 'cold' meters around the rev limiters).

I limped the car to the side of the road and called for breakdown recovery.
The recovery arrived, and using 'non-bmw' specialist equipment found no OBD codes (although there may be some recorded only accessible with BMW kit).

Whilst waiting, and with the engine off, I noticed the 'START/STOP engine' button flickering.
It was flickering pretty erraticly. I started the engine, and the engine was dying in line with the flickers from the 'START/STOP' button flickers.

So.... I'm thinking it may be a problem with this button mechanism (given as the key now once again reads 999999, and my windows drop again!).
Is this the CAS module?
Does anyone think it may be this?

Could it be that the whole bus is being starved of power? or possibly a faulty CAS module which is giving me ignition issues?

Very strangely, when I got home, I started the car, and it idled perfectly - no blips no problem.
Seems like the problem is very intermittent, and possibly only occurs when the car has run for a number of miles (??) - Still a bit baffled, but my dealer was pretty clueless when I went to them the first time.

Any advice appreciated.

Thanks

Hi Chumpy not the kind of problem you can live with or drive around with. You mentioned you have disconnected your battery for some hours and that seemed to help for a short while. Yes correct voltage is the key but also to get rid of ANY electrostatic charge on your system. Disconnect your battery and short the - and + leads together for 10 seconds. Reconnect battery and re-check your car. Please let us know if ANY after market equipment was installed or connected to your wheels, Have you been a good samaritain and jumped started someone else? New alarm system or sound fitted?
Good Luck!

Thanks for your reply and input.

I was advised by BMW not to short the 2 battery terminals together, and am 'kind-of' reluctant to try to be honest.

The car does have a Tracker device on it with remote imobilisation capability.
I'm contacting them to run a diagnostic on their device.

Does anyone think it may be the CAS module?
It seems common to the issues of:
- Ignition fault
- Reading wrong mileage from the key
- Dropping the windows when I remove the key.

Any help appreciated.

You can take your wheels to auto electrician to get the electrostatics removed. But now that you mentioned the tracker addition to your wheels, for the diagnostics of your problem have the system disconnected from your electrical circuit ( COMPLETELY ) as if it was never installed in the first place and run your wheels for some time, you could be in the pound seats again.
Keep me posted

Thanks for the reply.

The tracker device was fitted about 16 months ago, and hasn't been a problem. I guess there is something on the ignition circuit thats gone t1ts up!

I'm not sure if the tracker is to blame, the CAS module, the battery etc etc....
Would be good if these cars just worked! Great cars..... under-developed software and electrical issues are a pain in the 4ss!

I will dig around a bit more. My B/ in-law is a BMW comp wizz kid I'll drop him a mail and see what he can come up with He is with BMW South Africa Auto Electronics Trainer.