Auxillary Battery Voltage

owencardew · 03-08-2016 08:33pm

Hi,

Could anyone savvy with their Evoque possibly check the voltage on their Auxillary Battery situated kind of below/behind their glovebox?

I have an inkling my issues with my Evoque could have something to do with this battery...

When the car is switched off, my Auxillary Battery shows 12.02V...

Appreciated!

PhilSkill · 03-08-2016 11:34pm

What voltage would you expect when switched off from a 12v battery?

owencardew · 03-08-2016 11:48pm

According to Topix an Evoque requires a minimum of 12.5V to not record a Low Voltage Error. So if the voltage is at 12.02V it is below that threshold. Hence why I asked what Voltage other peoples Auxiliary Batteries are showing as a method of deducing a dud Aux Battery and understanding the variation in other peoples batteries.

xoz · 04-08-2016 12:07am

3 times my12 was at the dealers because Start/stop function wasn't working. Twice they checked the auxiliary battery, it read ok. 3rd time they decided to replace it. Start/ Stop now works perfectly.

PhilSkill · 04-08-2016 12:29am

12.0v is pretty much dead/ empty, you should see 12.4v up to ideally 12.8v particularly if just run,

some have disconnected their Aux Battery to disable S/S.

owencardew · 04-08-2016 04:54am

I dont have the Stop/Start function on my Evoque however it seems that battery has something to so with the transmission because this guy in florida had the exact same problem i have been having except the leads on mine are still connected hence why i think the battery is dead...

http://www.evoqueforums.net/forum/evoque...rning.html

@Philskill, i have just seen your post about Stop Start disabling - this is not that small battery next to the main battery. It is a smaller battery situated behind the glovebox about the size of a box of cigarettes...

owencardew · 04-08-2016 06:27am

This is the Auxiliary Battery I am talking about - not much bigger than a box of cigarettes, and is situated behind the glovebox but accessible via the footwell. From the diagrams I looked at yesterday, it seems this unit is responsible for the TCM and the GSM Modules.

As of this morning before starting the car for its first time today, the voltage was at 11.97V - probably too low and the reason for the error on my dash.. makes sense that once you start the car and drive it around a bit, it charges up, and the fault goes away...

PhilSkill · 04-08-2016 08:56am

Ah, ok wasn't aware of that battery... did wonder when you said below/behind glovebox.

Under 12v is not sounding good, guess no harm in replacing it and seeing if that solves your issue, given it's done 4 years, probably be all the better for replacement anyway.

Not liking having so many batteries on modern cars, life span of batteries is notorious.

Steve D · 04-08-2016 08:59am

Do they all have that battery? What will still be live when the main battery is disconnected?

xoz · 04-08-2016 10:59am

(04-08-2016 04:54am)owencardew Wrote: I dont have the Stop/Start function on my Evoque however it seems that battery has something to so with the transmission because this guy in florida had the exact same problem i have been having except the leads on mine are still connected hence why i think the battery is dead...

http://www.evoqueforums.net/forum/evoque...rning.html

@Philskill, i have just seen your post about Stop Start disabling - this is not that small battery next to the main battery. It is a smaller battery situated behind the glovebox about the size of a box of cigarettes...

I honestly thought Start / Stop was standard on all models especially Dynamic.?
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