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Hi Guys, UPDATED: I have created the guide and it is attached here
My Bentley GT (2005, UK Model) Main Battery keeps losing charge and dies. I don't really want to go to the dealer as they are charging a whopping £400+ to replace it which is ridiculous and another Bentley dealer 200 miles away from me is asking £226 but it's to far for me.
Can the main battery be changed without going to the dealer?
Does anyone know how to remove battery? As it's got some wires attached to it.
See the pictures attached
I will also create a guide for people once I figure out how to change the battery.
Last edited by samy999; 07-20-2015 at 04:17 PM.
Reason: Added attachment guide
disconnect both terminals isolate them so they dont touch the body and remove the battery.
Once the positive terminal is removed all the associated positive leads will flex to move out of the way
Make sure the steering wheel is straight and all the windows all the way up. Disconnect the battery and remove. Replace the battery. Be sure to wait 15 minutes. then reconnect the battery. Start the car up and drive the car around the block for the esp and traction control lights go off in the dash. Then roll the window down – when the window is down, hit the switch down again; then roll the window up and when the window is all the way up hit the switch up again to learn its stops. Do that for the other 3 windows same procedure above. Then pay attention to the clock - is the clock operational? When you connect the battery again the clock should go to 12 o clock first and then time should start.
disconnect both terminals isolate them so they dont touch the body and remove the battery.
Once the positive terminal is removed all the associated positive leads will flex to move out of the way
What I was told:
Make sure the steering wheel is straight and all the windows all the way up. Disconnect the battery and remove. Replace the battery. Be sure to wait 15 minutes. then reconnect the battery. Start the car up and drive the car around the block for the esp and traction control lights go off in the dash. Then roll the window down – when the window is down, hit the switch down again; then roll the window up and when the window is all the way up hit the switch up again to learn its stops. Do that for the other 3 windows same procedure above. Then pay attention to the clock - is the clock operational? When you connect the battery again the clock should go to 12 o clock first and then time should start.
Brian.
2008 GTC
Thank you very much guys for the reply. One more quick question do I need to do anything to the starter battery? Like disconnect it or anything? Or do I just leave it as it is, the starter battery is fully functional.
Many thanks again, going to order my battery soon.
I have a feeling that the starter earth should be disconnected first/reconnected last. Something to do with the pyrotechnic charge on the starter battery.
Have you considered an Independent Bentley specialist? Mine,'GT Services', is in Crewe and is brilliant.
1. Switch off ignition and all electrical consumers then remove ignition key.
2. Wait 60 seconds then disconnect the starter battery earth.
You can then change the main battery. There is also mention of checking zero steering calibration so maybe that's why you need the steering straight ahead.
As well as the windows, you may have to reset the seat memories/clock, etc.
1. Switch off ignition and all electrical consumers then remove ignition key.
2. Wait 60 seconds then disconnect the starter battery earth.
You can then change the main battery. There is also mention of checking zero steering calibration so maybe that's why you need the steering straight ahead.
As well as the windows, you may have to reset the seat memories/clock, etc.
Good luck.
Les.
Hi Les,
Thanks for the instructions. I managed to get it all done. Was fun actually and frustrating lol but got there in the end.
You were right about everything it was all reset to default so had to change things back.
The battery weighs a ton or its a sign that I need to hit the gym lol.
Thankyou samy999, this thread has been very helpful.
I have a question, in the foto you have posted of your main battery, the specifications are :
3D0 915 105 G
12V 85Ah 480A DIN
860A EN
So my question is if i get a battery with more than the 85Ah for example a 90ah and 800A, is that compatible? Does any one know?
So which would be the best out of these : https://www.norauto.es/catalog/260_M...ica-y-4x4.html
Thank you
The 800 figure represents something like the A available in cold, or something like that, not 100% sure.
I'm going to order the correct batteries and try out this DIY. I'm relying on samy999's pdf guide.
Good news, for the moment i have replaced the starter battery which seemed and was very simple and everything works fine.
I will soon order the new Varta AGM 95Ah 850 EN which is better than the OEM 85Ah that Bentley offers.
I would also like to add to any guide of the Starter Battery that there is a narrow flexible plastic tube that comes from the car (i think is the breather for any battery fumes) that has to be plugged to one of the breathing holes that the battery has in either side.
My main battery has been replaced recently and now I am getting a low battery warning again.
I keep the tender on all the time and it shows full charge.
Dealer told me the tender does not charge the battery on the right side??
Does anybody know why it is not set to maintain both batteries??
2009 Bentley GTC
I believe the battery on the Right side is reason for my Low Battery alarm since I have no problem starting the car and running - Low Battery message goes out.
I think it is the original battery which is amazing that it has not failed before - 6 years is good.
I will post later when I stop by the dealer.
07-16-2015, 12:55 PM
Low battery warning
