Secondary battery

[Carl Grundy]

Hi all

During a car service I was advised to.  replaced the main battery on my Jaguar 2.2 XF 2013 premium luxury which has been done.

Prior to having the service i had no heated seats, wing mirrors not defrosting along with rear window which is still the case.

i have been told I need to replace the secondary battery is this causing the issues I am having with the above?

Carl

[N6 JMX]

Hi Carl, not sure if your issues are battery related, but might be.

Have you checked the fuses, sounds like a circuit is out of synch.

If your secondary battery is still the original from 2013, presumably your main battery could also have been original equipment, then I would go for a replacement of the secondary battery. Modern cars, especially Jaguar are VERY sensitive to voltage fluctuations and a poor battery is a prime cause of these.

I believe the secondary battery only comes into play to feed the voltage sensitive circuits when the car is operating in start / stop mode. Does your start / stop mode operate under normal circumstances?

N6 JMX

[Carl Grundy]

Hi

thank you for the reply

stop/start is currently not working either 

[N6 JMX]

Hi Carl, it is by no means a certainty, but if your secondary / auxiliary battery has "failed" and therefore cannot provide the voltage to the sensitive electronics during stop / start activity, then that could be a reason as to why the stop / start system is not working.

I am sure others can comment further, but as far as I am aware, if the main battery has a decent enough charge for the brain to know it has the power to restart the engine + the secondary battery has the capability to supply the sensitive circuits during an engine stop, then, unless the start / stop has been disabled manually / switched off, then it should work.

Under normal situations when both battery circuits are good, there may be the odd occasion when the stop / start system is inoperable (The dash light is scored out) and this is due to the main battery being low on power for any number of reasons, typically too many earlier starts as may happen in crawling traffic.

N6 JMX

[Carl Grundy]

Thanks Jim

info very much appreciated.

Carl