Start/stop failure and EPC light

Dec 6, 2023
2
0
I have a SEAT Leon 1.2 TSI (2016).

I find the start/stop technology frequently doesn't work. It instead shows an A with a line through it and the engine stays on. That I don't really care about so much, I'm fine with just driving without it. When I did use it, it would often stop working midway through a trip and then cause other problems, the biggest of which was the EPC light coming on.

The EPC light would come on the dashboard and then for the duration of the trip I would have a loss of power, I wouldn't be able to get the revs high enough and in general couldn't accelerate or ever get over 40mph regardless of what gear I was in. From what I noticed this only happened when I was using the start/stop technology. Since I stopped using it, the EPC light hasn't come on.

Does this sound like something has gone wrong and I should get it fixed? It only really caused me a major issue once on the motorway, but then after pulling over and stopping and switching the engine off and then turning it on again the issue was resolved. I've afraid to even try using start/stop since because the loss of power on the motorway was actually quite dangerous.
 

SteveGSXR600K1

Active Member
May 6, 2017
579
189
Have you had the car long? The Stop/Start only works when several conditions have been met like car up to a reasonable temp, battery not under load from air con, etc. It sounds like either the battery is on its way out, or it has been changed and not coded in. Start with @tracktoy's suggestion and check for codes.
 
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romster1

Active Member
Nov 26, 2016
107
6
W London
I have a SEAT Leon 1.2 TSI (2016).

I find the start/stop technology frequently doesn't work. It instead shows an A with a line through it and the engine stays on. That I don't really care about so much, I'm fine with just driving without it. When I did use it, it would often stop working midway through a trip and then cause other problems, the biggest of which was the EPC light coming on.

The EPC light would come on the dashboard and then for the duration of the trip I would have a loss of power, I wouldn't be able to get the revs high enough and in general couldn't accelerate or ever get over 40mph regardless of what gear I was in. From what I noticed this only happened when I was using the start/stop technology. Since I stopped using it, the EPC light hasn't come on.

Does this sound like something has gone wrong and I should get it fixed? It only really caused me a major issue once on the motorway, but then after pulling over and stopping and switching the engine off and then turning it on again the issue was resolved. I've afraid to even try using start/stop since because the loss of power on the motorway was actually quite dangerous.
the epc light has just started coming on in my MK3 1.8 but I'm not having any issues with accelerationism not sure why you would have had acceleration issues as the stop start system, from what i can tell has a separate battery so your main one would have been OKwhich seems to be the caser with mine as the car is driving fine without any issues at all despite the EPC light
 

Big Vinny

Active Member
Oct 14, 2012
215
44
The stop start will stop working when the battery ages and will not hold full charge. The stop start on our 2020 Ibiza has not worked for over a year as we just get the "A" symbol with a line through it. As I understand it when the charge level falls below 80% the stop start will not kick in. The solution is a new battery but I will wait for the old one to die first.
 
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