Bentley Continental GTC Low Battery

Bentley Continental GTC Low Battery

Author
Discussion

nailya

Original Poster:

56 posts

152 months

Monday 25th February 2013
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Does anyone know at what voltage does the battery low warning trigger on a Continental GTC? I know that the normal operational voltage is around 14.4V

MrC986

3,559 posts

198 months

Monday 25th February 2013
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I don't know the answer to your question though I do know if the battery is low it throws up warnings like brake failure & even rear brake light failure. If you can, get a battery conditioner & hook it up overnight every so often & do both the main battery & the backup one.

nailya

Original Poster:

56 posts

152 months

Monday 25th February 2013
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I have been told by Bentley dealer that the trickle feed unit supplied with continentals is designed to simply maintain voltage. It will not recharge batteries apparently. Seems very peculiar to me.

MrC986

3,559 posts

198 months

Monday 25th February 2013
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I have an Optimate & it definitely sorted my friends BGT when he went on hols & left it with me to charge up/clean! l put the main battery on charge for about 36 hrs BTW.

RevHappy

1,840 posts

169 months

Saturday 2nd March 2013
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The warning signal pops up on the dash if your running low, they are very power hungry cars.
There's a 12v in the boot if you dont want to buy the bentley charger.
If you do get stuck, turn the key the other way and it will start using the other battery.

bertie

8,566 posts

291 months

Saturday 2nd March 2013
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RevHappy said:
The warning signal pops up on the dash if your running low, they are very power hungry cars.
There's a 12v in the boot if you dont want to buy the bentley charger.
If you do get stuck, turn the key the other way and it will start using the other battery.
The other battery????

nailya

Original Poster:

56 posts

152 months

Saturday 2nd March 2013
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Bentley Conti's have two batteries. The back up battery is also used to boost start up etc.

bertie

8,566 posts

291 months

Saturday 2nd March 2013
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nailya said:
Bentley Conti's have two batteries. The back up battery is also used to boost start up etc.
Really? I knew Arnages did but didn't know Continentals did.......slopes off to look under boot floor....

nailya

Original Poster:

56 posts

152 months

Saturday 2nd March 2013
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the second battery is housed in the right hand side of the boot and not usually accessible

NDA

22,335 posts

232 months

Wednesday 6th March 2013
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I no longer have my GTC, but seem to recall turning the ignition key anticlockwise will allow a start from the second battery.

The trickle won't bring back a dead battery, but it keeps a decent condition battery topped up. Is yours not keeping its charge?

nailya

Original Poster:

56 posts

152 months

Wednesday 6th March 2013
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I am familiar with the second battery usage but this is not the problem I have experienced. The main battery loses power very rapidly and with no warning, particularly during cold weather.

The first time this happened it was found that the main battery had been drained but the back up still had plenty of life left in it. The relay triggered by the key did not seem to work.

NDA

22,335 posts

232 months

Wednesday 6th March 2013
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Knackered battery then.

I suspect a damaged cell - I had this with my RR last year, the battery was always giving problems.

nailya

Original Poster:

56 posts

152 months

Wednesday 6th March 2013
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Bentley say otherwise - basically telling me nothing wrong except lack of use on my part as well as not using trickle feed. Followed their recommendations to the letter but same thing happened last November since when the car has sat dead on the drive

NDA

22,335 posts

232 months

Thursday 7th March 2013
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nailya said:
Bentley say otherwise - basically telling me nothing wrong except lack of use on my part as well as not using trickle feed. Followed their recommendations to the letter but same thing happened last November since when the car has sat dead on the drive
Once a battery has been flat, it gets damaged.... It's never as strong as it once was, wont hold it's charge and lacks the CCA (Cold Cranking Amps) needed for a big engine. That's why it's important to keep it on a trickle, to keep it topped up. But, as I say, once fully depleted, the battery can't really be restored - its the equivalent of a cardiac for the battery.

Do you know anyone with a load tester who can give you the CCA reading on that battery? That would tell you for sure if the battery has failed or not.

If you do buy a new battery, ensure it's kept on the trickle and it'll be trouble free.

There's the outside chance that your alternator is knacked - but on a Bentley, I'd say this is a really very remote possibility. Put a voltmeter on it on tickover and the alternator should be putting out just under 15v.

nailya

Original Poster:

56 posts

152 months

Thursday 7th March 2013
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Thanks for this.

I think, but not 100% sure, that the main battery was changed February last year after the first shut down. The car then stayed put at the dealer for about 10 weeks as I told them I did not want it back after the numerous problems, most of which were repetitive.
As discussions progressed with Bentley on this, the dealer was instructed to return the car to me and to this end agreed a time etc with me for the car to be delivered. The transporter arrived at the dealer to pick up the car but after an hour or so was turned away. He was given no official reason but learned from the technicians that the car would not start as the battery was flat!!!

The car was picked up the next day and sent back to me.

I asked for an explanation and was told there was no real problem but a decision was taken to check the car over and make sure there was 100% charge etc.

To me several issues here - why were the checks not done so the car could be delivered on time? - why was the battery flat? - could it be that the car had shut down on the dealer as it had done for me a few months earlier, and again last November?

I asked if the trickle feed unit had been used whilst the car was at the dealer. I was told that they have over 100 cars on site and hence cannot confirm when or if this was done.

Clearly the dealer did not follow their own battery maintenance recommendations?

Incidentally I do not believe the owners manual contains instructions on the trickle feed unit or circumstances in which it should be used

NDA

22,335 posts

232 months

Friday 8th March 2013
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Does your GTC have a 'tracker' security type device fitted?

nailya

Original Poster:

56 posts

152 months

Friday 8th March 2013
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NDA said:
Does your GTC have a 'tracker' security type device fitted?
YES IT DOES

NDA

22,335 posts

232 months

Friday 8th March 2013
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This is what's causing the flat battery.

I have had several cars with trackers, and they have to be kept on a trickle charge.

nailya

Original Poster:

56 posts

152 months

Friday 8th March 2013
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NDA said:
This is what's causing the flat battery.

I have had several cars with trackers, and they have to be kept on a trickle charge.
This is the 5th car I have had which is fitted with a tracker. I have had a Q7, Porsche Cayenne, Range Rover Sport and 2 GTC's. All of these cars contain similar high tech equipment.

The current GTC is the first car I have experienced any electrical issues with.

I know that the likes of the tracker and alarms draw on the power when the car is parked up but if these were the cause of the problem I would have expected the car warning system to advise of low power a decent time in advance of the complete shutdown of the car. In the two instances that I have witnessed the shutdown no warning was given. I also suspect that when the car was with the dealer the warning also failed as clearly they were taken by surprise and had to delay the cars return to me.

gentlybentley

5 posts

156 months

Thursday 22nd August 2019
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I changed both batteries last November in my Supersports and have had it on battery maintenance charge every other weekend. This morning the "Battery low" warning light came on instructing me to start the engine. When I got to work I put the charger on for 8 hours and it showed charged condition. I disconnected it, got in the car and the warning light came up again " Low battery, start engine".