SEAT Leon FR 2019 randomly braking, brake lights randomly switching on and off.

[alixoconnor]

Hi,

I have a 69 plate SEAT Leon FR Sport with incredibly low mileage (less than 20k) and I want to preface this by saying I have minimal car knowledge!

A couple of weeks ago it started to randomly slow down whilst I was accelerating, I initially thought it was losing power but have now realised that it's very gently braking and cutting my acceleration. Sometimes the EPC light switches on, sometimes the engine warning light and sometimes nothing at all. I asked my girlfriend to follow me in the car and we've also noticed that the brake lights randomly switch on and off intermittently (staying on 80% of the time, no trend to it switching off)

I've been up and down to the garage multiple times, always having different fault codes come up during diagnostics. We've replaced the battery and the brake switch and neither have fixed it. Now they've sent it to an auto electrician that has come back saying that it's an issue with the brake master cylinder, which SEAT have changed to operate differently to the standard setup? They've also checked with their parts dealer who has told them that there's been a massive increase in SEAT Leon's needing that particular part replaced, which usually is never needed.

Does anyone know if SEAT are aware of this? It doesn't seem right to me to have to pay for a fault that is entirely beyond wear and tear and not caused through any fault of my own. It's quite simply a manufacturing failure as far as I'm concerned.

Just feeling really lost and like the car's becoming a money pit, we've just paid off the finance and are now pouring money into it to fix a problem that we can't diagnose and doesn't seem to have a guaranteed solution.

Thanks,
Alix

 

[RUM4MO]

I don’t want to depress you any more, but, from what I’ve read, VW Group especially in UK, aggressively deny any annoying faults that have not yet been “pinned” on them by DVLA, and so are not interested in helping you, money wise, in replacing any parts that have required revising to stop this situation arising.

Edit:- even if this is a known fault, most main dealership’s service area will claim that you are the first to report this.

Hopefully someone within one of the VW Group forums will guide you to getting it resolved quickly.

 

[Mr Mustard]

Which engine is this Alix?

 

[DEAN0]

I would be tempted to have a look at the brake light switch at the pedal.
If there is a loose wire - it could be touching something to bring on the brake lights.

Modern cars also cut engine power when you go for the brake pedal.

 

[Seriously?]

I would be tempted to have a look at the brake light switch at the pedal.
If there is a loose wire - it could be touching something to bring on the brake lights.

Modern cars also cut engine power when you go for the brake pedal.

I've had trouble with VW group brake light switches failing internally in the past, but these were the pedal mounted switches. Does the 5F Leon have the brake light switch on the master cylinder?

 

[redone]

sounds like some wire(s) is shorting out intermittently as you bounce down the road. or perhaps the/an ecu is a bit fried.

sounds (potentially) dangerous af to drive. you need an auto electrician, not the one used so far, ideally familiar with vag cars, to methodically go through things.

failing that it may be easier to trade it in (or wbac, or auction) and just get a car without such an issue.

 

[DEAN0]

I've had trouble with VW group brake light switches failing internally in the past, but these were the pedal mounted switches. Does the 5F Leon have the brake light switch on the master cylinder?

You are correct - switch is attached to the master cyl