Start-stop fault?

Hi

I've just picked up a used Audi A7 (2014 black edition 3.0 bitdi) from an Audi dealer at the weekend.

I don't have any fault warnings but I just can't get the start-stop system to kick in (it has actually worked at one junction but that is all). I know the car has to have enough power and the conditions have to be right but I have done several journey with the conditions below and every time I stop I get the white Start-stop logo with a line through it appear on the dash:
45+ mins driving
Comfort/efficiency mode in drive select
Tried turning off everything included AC, heated mirrors, radio

I'm wondering if the dealer supplied the car with a duff battery that stops the system working?

I'm going to go back to dealer but wanted an idea of what it might be incase they try and fob me off.

Thanks

 

Hi, try this link it may help. https://www.audi-sport.net/xf/threads/dodgy-batteries.383892/#post-3516123

 

Could be as simple as the last owner coded the start/stop button so it reversed.


A7 3.0tdi 272 Black Edition Mythos Black Tech pack

 

If it’s not working after trying with both light on & off (start stop button on dash) then i would suspect a duff battery.

 

I think a car dated from 2014 with a start stop issue does not denote a dodgy battery, just one that may have had some abuse in it's time. Would be a good idea to get the battery checked anyway, you can get this performed for free in some places...

 

Dont have to code anything to disable the start stop.

Unplug the charge level connector cable from the battery and it makes the car think the battery level is too low to enable start stop.

This is what a main dealer told me as they questioned why mine had been disconnected, not that i knew or cared anyway lol

 

I've had it working on a couple of journeys. But I would say it has only kicked in about 5 times in the last week of driving every day. It can work so I know it isn't switched off, I'm just thinking the battery doesn't have enough guts left. If the battery is 5 years old it would be due a replacement anyway.

 

Doesn't it put any lights or warnings on the dash ?
The stop start on my A7 works fine but does my head in, I would love to disable it for good.
Which wire is it on the battery?

 

As others suggest, get the battery checked to rule it out if nothing else, I would have thought however that if this was low in power you would get a message on the dash.

 

You can use OBDeleven to turn on memory function for Start/Stop so it’s always off if you choose it.

 

So I just spoke to Maidstone Audi. They said there is probably nothing wrong with the car if there are no warning lights. There are apparently "50 reasons why the system wouldn't operate including if the radio is on"! It's a joke. No way could Audi have designed a start stop system that doesn't work if the radio is on!

I still need to get the battery checked but want to get Audi to pay for the diagnostics as the issue has been there since I bought the car 2 weeks ago.

 

Could be temperature related this weather, if it's too cold it won't kick in.

 

Just a thought but if you have the heating set to Auto.
It wont stop start when the Aircon is on.
Have you looked ?

 

In auto start/stop works ok with my car...

 

Sorry maybe I wasn't clear.
Heating on Auto (not the engine/gearbox) occasionally allows the air con to kick in.
When this happens the stop start will not work.
The aircon button will show red, same time as auto on heater control panel.

 

The Start/Stop does work with Aircon on, but it may not work if cabin temperature isn’t the same as selection on climate control. My car starts up itself sometimes at the lights because of this.

 

I live and learn !
Thank you.

 

None what so ever.

Dont know which wire as mine mustve been done by previous owner.

 

Plus if the CC is set to 'Hi' or 'Low' start/stop is disabled and, if you've three way CC, check the rear passengers one isn't set to Low or Hi either...