Low battery error.

GARETH · Post by **GARETH** » Sun Mar 21, 2021 2:34 pm

First of 2 problems today. Low battery start engine message about 20 seconds after shut down. It appears on the centre display and stays on until the car goes to sleep. However the car seems fine and gives no hint of a flat battery. It usually has a trickle charge on it. It started doing this even after a long drive.

Tested the volts and it’s steady at 12.7 engine off and car asleep. The only suspect part of the test was the cranking volts dropped to 9 and my tester logged that as a fail. The charging volts engine running at idle are 14.9 - 15.1.

It is an original battery from 2014, but has not done a lot of miles 35k and usually has a conditioner on it.

Other than a diagnostic session, is there any other way of resetting the battery management system? I suspect it’s lost it’s way with the battery condition over the winter.

scm · Post by **scm** » Sun Mar 21, 2021 3:20 pm

7 years is good for a battery, I'd suspect it's getting tired.

Tel · Post by **Tel** » Sun Mar 21, 2021 3:57 pm

The Fiam AGM's tend to go downhill after around the 3 year mark, irrespective of mileage.

Always carry a small adjustable to whip the +ve battery terminal off the battery for half a minute, have a brew. reconnect et voila.

GARETH · Post by **GARETH** » Sun Mar 21, 2021 4:35 pm

That simple. Ok I’ll give it a go.

cj10jeeper · Post by **cj10jeeper** » Sun Mar 21, 2021 6:48 pm

scm wrote: ↑Sun Mar 21, 2021 3:20 pm 7 years is good for a battery, I'd suspect it's getting tired.

I'd agree - time for a new one at 7 years before looking for deeper issues

It may well hold the voltage but it won't deliver the amperage either due to the battery or possible poor connections
Had the same on my Evoque and only 4 years. New one and no low battery errors since. Old battery still reads perfect 1t 12.6 after 4 months in the garage

GARETH · Post by **GARETH** » Sun Mar 21, 2021 8:00 pm

Does anyone have the spec of the battery I need? Save me going out to the car to look! I can order one whilst watching Top Gear

scm · Post by **scm** » Sun Mar 21, 2021 8:28 pm

https://www.tayna.co.uk/car-batteries/types/019-agm/

Duvetday · Post by **Duvetday** » Tue Oct 01, 2024 10:09 am

GARETH wrote: ↑Sun Mar 21, 2021 4:35 pm That simple. Ok I’ll give it a go.

Did disconnecting the positive on on the battery for 5 mins work to reset the battery management ?

scm · Post by **scm** » Tue Oct 01, 2024 10:21 am

I don't think it even has to be for 5 minutes - 1 should be enough. Don't close the boot lid while the battery is disconnected, though!

gasgas · Post by **gasgas** » Tue Oct 01, 2024 2:28 pm

no brainer, new battery

Low battery error.

Jaguar F-Type Forum