The EPC warning light with start/stop fault error has just started coming on once every few weeks over last few months does anyone know what causes this and is it anything to worry about ? It goes away once restarting the engine and drives fine, i always turn the start/stop off everytime i get in the car, only time i use it is if stuck in a que at a drive thru but noticed sometimes while not moving with start stop switched on the engine will restart on its own after a minute or so without me pressing the accelerator, not sure if this is related to the start stop fault i’ve been getting, car is a 2014 1.8tsfi a3
EPC light + start/stop fault ?
- Thread starter Audicfc
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Engine will switch back on if battery charge too low or A/C requires it etc, so that's normal. I'd probably suspect battery as a first port of call, when was it last changed? Mine lasted six years until it started doing spurious things (same age and engine as yours but quattro).
Have you had your thermostat / water pump changed yet? When mine was on the way out and leaking into the wiring connector underneath earlier this year I got all sorts of EPC warnings and car would sometimes go into limp mode, thermostat went either high or low etc. Unfortunately a design fault with that engine and if it hasn't happened yet, it will. I was looking at the thick end of £1400 once the wiring loom had been repaired and the thermostat assembly and water pump replaced.
Really, you should get it scanned to see what the car is reporting...
Have you had your thermostat / water pump changed yet? When mine was on the way out and leaking into the wiring connector underneath earlier this year I got all sorts of EPC warnings and car would sometimes go into limp mode, thermostat went either high or low etc. Unfortunately a design fault with that engine and if it hasn't happened yet, it will. I was looking at the thick end of £1400 once the wiring loom had been repaired and the thermostat assembly and water pump replaced.
Really, you should get it scanned to see what the car is reporting...
I presume it’s the original battery that is still in it, i bought the car when it was 5 years old with 30k on the clock, i’ve had it for just over 3 years now and its at 55k miles now i thought the battery would last a bit longer than this
yes i had to get the thermostat and waterpump changed not long after buying the car which i think the previous owner knew about as it was a private sale, cost me £675, that was about 3 years ago so i would be very disapointed if its started leaking again but coolant level looks normal and temperature on dashboard is where it should be, althought i’m certain putting the heating at 22 degrees used to blow out a bit warmer air than it does now but can’t be 100% sure on that one, car has cost me a good bit on getting stuff fixed line needing 2 new rear calipers over the past 2 years and drinks atleast about 4 litres of oil easily over a year, does your 1.8 consume a lot of oil ?
Nope, my engine doesn't eat any oil at all. If it's the original battery, it's well past its expected life. When I posted that I was changing mine after six years, a lot of people expressed surprise that it had lasted that long! 
Also, given the age and model, definitely worth checking this as a matter of course (unrelated to your current issue):
www.audi-sport.net
Help! Fuel Leak!
Well, that was “fun”. Drove into work without issue. Went to drive home and the car started and then stopped. Started it again, it stopped again. Massive smell of fuel. Popped the bonnet, fuel pooled in the wells of the inlet manifold. Popped off the cover and found the pressure switch in the...
How much would it be for a new battery and is there any specific brand to go for ? Seen halfords have one for £151 and £25 for fitting it
Just had look at your other post there i will have a look at the clip in next few days when doing my monthly oil level checks
Just had look at your other post there i will have a look at the clip in next few days when doing my monthly oil level checks
You probably can't buy the OEM brand in the UK. I bought: N70 Varta Start-Stop EFB Car Battery 12V 70Ah (570500076) Type 096 from tayna.co.uk and fitted it myself. Don't be surprised by the Christmas tree of dashboard lights that illuminate when you turn the car back on, this is normal and they go away within a few seconds of driving off. The one that took longest was Stop/Start which took about 20 mins, but once it had reset it was literally going into Stop/Start from cold at the end of the road rather than after about 15 mins as it had been before the battery change. I know you don't use the function anyway.
A poor battery can mean the voltage drops below a critical level while starting, or cranking as they say in the US. This short term unstable voltage can cause all sorts of faults to show up, often in the abs system and other control units, as sensors temporarily don't respond correctly. If you have an OBD scanner like OBDeleven, you might find more intermittent fault codes that don't show on the dash. My battery is original almost 8 year old agm, it is fading, and I have by times got a fair few faults when starting after a period sitting in the car playing with the media system, Google maps or android auto. A slow crank almost certainly produces an engine sync timing error I get intermittently. which could be construed as needing a new timing chain, ££€€€$$, but it is intermittent and most likely poor battery on starting.I'll change it soon, ( battery, NOT chain!), hard to do when you're a cheapskate though.
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Changing the battery in mine, coding it and removing start/stop function fixed my EPC issues in my S3
Had a similar issue with the EPC and the start/stop not working. Started off as intermittent fault with the EPC light and then it came on all the time.
Took it to a garage who scanned it and it came back as a Turbo Actuator fault.
The garage replaced this and since then no more issues, EPC light has gone out and start/stop is now working again.
Yes it has started to come on every couple of days now but i just restart engine and it goes away, car doesn’t feel any different to drive that it usually does, how much did it cost to fix the turbo actuator fault and was there any difference in driving the car from before and after you got it fixed ?
Still not got a new battery for it anyway as some websites say i need an agm and some say i need an efb, then some say it needs coded and others say it doesn’t
Any decent battery supplier will Identify your battery from its labels, but it most certainly is an AGM battery if you've got stop start. There are battery settings in the cars control units, some cars have battery management controllers so can optimise charge cycles. I'd expect it in an AGM equipped stop start car. If there's small plugged in wire on the main + battery terminal, that's an indicator of a battery management module. If you replace the battery with the same capacity and type (AGM), then the coding will be substantially correct, but if you want you can find someone with an OBDELEVEN coder or VCDS and they can set the parameters in Adaptations in control unit 19, Gateway. I've only heard of issues talking to my motor factor, when people replaced AGM with cheaper lower capacity standard, and the AGM charging pattern was too much for the ordinary battery, and done it in in 6 months.
I'll put my OBDELEVEN on mine and grab the screen related to this later.
Btw, TFSi do use a lot of oil, my previous A6 was 2l TFSi, fabulous drive, especially with CVT transmission. I just kept it topped up. It never smoked or affected emissions test at the test centre. It appears to be a very common trait on these engines. Your oil is always fresh too, as it used about an oil changes worth between service intervals, oil would come out really clean when changing. Now that I think if it, I used to get those intermittent faults in that car, warning light, even a drop in response, which went away when on restart, and when I eventually put in a new battery.
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Yes it has start/stop but the yuasa website says i need an agm battery but varta website recommends the efb as 1st choice but also gives option for the agm version aswell, my current battery says its an EFB Moll battery which looks like the original battery which would be 8 years old now, so that’s why i’m getting a bit confused as to what battery i really need
If your current battery is original and not an AGM, then you can replace it with the original EFB type (EFB is an Enhanced version of an ordinary Flooded Battery) or AGM. If you get a battery with the same Ah rating, or slightly higher, you won't need to program it. I just checked my own battery entry using OBDELEVEN scan tool, and it returned battery Ah of 95, manufacturer and serial code. There was no facility to program other type. This means my battery management system is fixed for AGM, so I must purchase this type. I do have the facility to program for a lower power, so if I replace my 95 with an 80ah, I must reprogram. Otherwise I can just put in a 95 or greater AGM, and no harm will come to the battery. Its generally good though to inform the system that the battery is new, but from what I'm reading it adapts to the charging characteristics of the replacement, assuming you put back the same rating and type.
Halfords as you say will install a new battery for a fee, but will also code it if required. You don't say what Ah rating is on your battery, but the battery filter by car model on Amazon is showing a Varta 70Ah, AGM, or a cheaper Dynamic brand enhanced calcium type as a fit for your car. As your car is not originally configured for AGM, you can safely replace it with EFB, AGM or Calcium.
Fwiw, I also read the charge capacity of my almost 8 year old battery using the scanner, and it read 17Ah, from the original 95, so I'll have to get my finger out and replace before a severe cold morning.
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