ESP Fault Light

[RJW]

Hi all,

While driving home last week, the ESP light appeared on the dash. Clicking the ESP button didn't switch the ESP light off. After I got home I realised that the brake lights were not lighting up when the brake pedal was pressed (but the centre brake light is still functioning normally). The globes themselves still work. I have since put a new brake light switch in but it has not changed anything.

The car in question is a Polo GTI 9n3.

Any ideas?

[sambb]

either you have a rear globe out, your brake switch (above the pedal is gone) or your MAF sensor is dead. Start with a globe check. If ones out replace the globe but I think you may still have to clear the error.

[sambb]

sorry re-read and you said you could already see that your outside two brake lights werent coming on. So I'd test that those globes are ok ie in another car. Even if the driving light side of them is ok it only takes one element to be gone to stuff the brake circuit. If they do test ok though then its probably the brake pedal switch but maybe there's a seperate fuse in there that I dont know about. Try reseating the plug, just the plug though. If you remove the sensor itself (its a twist style like a bayonet light globe) it will break the tabs on it and it wont work afterwards. So make sure you've ordered a spare before you remove the existing one as its virtually guaranteed not to work ie it may take out the centre brake light too, if you try to refit a removed one.

[simon k]

it shouldn't be the switch because the centre brake light is working.. I'd check for any codes from the brake control module, or do a scan of the whole car. There will be fault codes somewhere

[sambb]

Yeah you’re probably right simon. The switch does have multiple contacts so maybe, but most likely they are for esp, abs and all rear brake lights as a group. But I have had this exact fault when a globe went and also when my maf sensor died the esp dash warning came on as well.

[h100vw]

Did you scan it to see what the ABS says is wrong? I'd have a look at the strip fuses on the battery. I am pretry sure one is for the ABS. If not those maybe the blade fuses .
Also, does your cruise control disconnect when pressing the clutch in as well as the brake? Can't recall without looking at the diagram if that's related too.

[RJW]

Thank you all for the suggestions.

I ran a scan initially and was getting a code for the brake light switch. I had ordered a new one through the dealership and put it in. Yesterday I ran another scan and a whole bunch of faults then began to pop up including the ABS, traction control, engine control module, indicators and even the airbags, which I thought was a bit odd. That evening I reseated the fuses, relays and the bulbs whilst putting the original brake light switch back in. This has so far resolved the issues and none of the fault codes have returned. Fingers crossed it stays that way.

[sambb]

Could be a hairline fracture in one of the battery mounted fuses which Gav referred to. Hasnt happened to me but plenty of people have suffered from this where a cracked fuse intermittently causes connection problems. Getting all those faults like that points to something there. just need a good torch, flip the lid on them on top of the battery and have a real good look at the fuses looking for a crack.