I've noticed the aux battery mentioned here before and never thought much about it. Now I'm curious what it's for, why it's there and where it's located in the car? I'm pretty sure my F-type doesn't have one, but am I missing something?

 

It's only in older versions of the car. I forget exactly which year they phased it out. I know 2014 and 2015 have it for sure. For coupes, the aux battery is located in the trunk, towards the back right of the car. It is a really dumb system and it is solely used for powering auxiliary components when the car is using the stop/start mechanism. The logic is the secondary battery powers the other systems since the main battery needs all its juice to restart the engine when it's time to start rolling again.

 

Thanks Whalesmash, good to know. Being third owner I'm sure a prior owner disconnected the stop/start. The light on the button lights up then goes out shortly after startup. Fine by me. Mine is a 11/15 build, MY 2016. I did find some extra cables in the undertray which I assume are for a trickle charger, though no charger is present.

 

It doesn't look like yours has the aux battery. In my car it is where the red box is pictured below:


Here's a link to the battery in case you're wondering. (For anyone else, don't actually buy it, it's over priced haha)

Edit: As a side note, there's a plug on that silver bit right under where I put the red box. Yours is unplugged, and that is the start/stop plug, so yes, your start stop is disabled

 

Looks like your previous owner had hardwired in the pigtail for a Deltran battery maintainer (which is highly recommended for these cars if it is not your daily driver). So all you need to do is pick one up and connect it to that black pigtail plug and you're in business.

 

2016s did not have the aux battery.

I can also see your stop/start is indeed unplugged, which is a good thing, IMO.

 

Thanks fellas!

 

That black cable also looks the same as for the Battery Tender Jr. that I use.

That silver box in the upper left is what replaced the aux battery. It’s the Voltage Quality something something (to lazy to look up its full name.) It’s a DC/DC converter that produces a solid 12V+ to power the car’s electronics during a restart.

And you have the same Duralast battery I put in mine 5 years ago.

 

Yes, all the Deltran maintainers use the same connector.

 

Let’s be precise: a trickle charger is NOT what is needed. Chargers like the CTEK and, I assume the Deltron, are battery MAINTAINERS. Quite different!

 

Those cables look like they are from an older Battery Tender brand charger. I have one of those but don't use it anymore. If you're looking to get a battery maintainer of some sort, most here seem to recommend C-Tek. I've got one for conventional and AGM batteries and another for lithium batteries and am quite happy with them.

 

Correct. I meant maintainer/tender and edited my posts accordingly.

 

Aux battery was for start - stop. I had it replaced on warranty once and the second time just disconnected it.