auto gearbox warning light

[Johnbmwz4]

Hello, I have an auto 3.0 SE on a 54 plate which is fantastic apart from every now and again when I start it the auto gearbox warning light comes on. When I turn it off and then back on it disappears. I have driven it once or twice with the warning light on but it puts the car into safe mode and keeps the car in 3rd gear ( i think) and the parking sensors don't work and gear display on the dash is just blank. When the warning light is not on the car drives perfect with no dodgy noises, changes gear when it should, sport mode working and parking sensors working. Im hoping its just a sensor or something as it is not on all the time. Any ideas??

Thanks

 

[TR4man]

Just guessing, but do you have a leak and the gearbox oil wants topping up or changing?

 

[firebobby]

That's what I was thinking

 

[Johnbmwz4]

Hi I have no oil leaks on my drive and I got the car serviced at my local garage when I first got it around 3000 miles ago and asked about getting the gearbox oil changed but they told me the gearbox is a sealed unit so no option to change it. Are they wrong? They are a very good garage and have used them for years but if they are wrong I will ask the question again to them.
Thanks

 

[DMike]

Mine had similar symptoms with transmission fail safe activating once or twice a month and lately every second day. The error light would come up even prior to starting the engine and just cycling the ingition off would help. INPA indicated problems with the transmission position switch confirmed at service. They didn't have the spare part and car is SORN now but I'll have the switch replaced in the spring.

 

[DMike]

To add, fail safe never happened after the starting, just prior or at starting. Mine's a pre facelift.

 

[Johnbmwz4]

Ok thanks, I mentioned it to my garage who told me to bring it in when the warning light is on and they will put a fault code reader on it, without the light on the code reader may not pick the fault up unless it is logged somehow. I will take it in the next time it comes on and let you know how I get on.

Thanks

 

[DMike]

I've had the error appearing sporadically for years and looked up with INPA myself. The error codes were logged but disappeared after a number (20?) engine starts.

 

[Ebeneezer]

My car does this too, and also my car does not have any issues once started. Odd times the light comes on as I switch off, after arriving at work. Car goes into limp mode if you try to drive it with the light on. The OBC stores 2 codes, one each connected to the auto box and engine. Another thing which happens is that after putting the lever in park and turning the motor off the car still moves a little when you release the brake pedal.

Tony.

ps. BMW say that the gearbox is filled for life but you can still drain, change the internal filter and re fill with new oil. I did my Z3.

 

[Midhurstman]

I have a 53 plate 3.0i auto and you can definitely change the oil in the auto box as I have had this carried by my very experienced Ex BMW indy (Andy at Walkers Autosport West Sussex). He agreed with me that it is probably a very good idea at 80,000-100,000 miles, even though BMW say its sealed for life. I also had the internal filter changed, quite expensive for the whole job at £180, but very well worth it. I remember an episode of wheeler dealers where Mike picked up a Boxster S for £1000 because the owner said it had an auto box fault, which caused it to play up badly. Ed changed the oil and filter and it was cured. So much for the manufacturers "it never needs changing"

 

[cusword]

I had this problem on an 05 3 litre auto. Fault codes reported a fault with the switch on the side of the gearbox that logs the position of the selector lever. You don't have to have the fault light showing to read fault codes. A new switch and no problems for six months.

The switch is fixed to the outside of the gearbox and has a short multicore cable with connector. You can do it from underneath the car.

Good luck......

David

 

[Scooba_Steve]

I believe that 'lifetime fill' actually means 100k. My interval for box and diff is 30k for peace of mind.