check brake pads (O) ... that’s the warning that came up on my display a couple of days ago. I was surprised at first, given that the car was serviced just 2000 miles ago, when the report given to me stated that front pads were 30% worn. :wonder:

It's not there all the time - some journeys it doesn't appear at all, and when it does appear, it's not when I brake (which is when I would have thought it should appear)

But then I realised that the pads were fitted 33000 miles ago.

• What percentage of useable pad is left when the sensor starts to work?
  
• When the pads are low enough - in use, when should the warning actually appear?
  

The pads are Tarox Strada and have been, and still feel, fine. Most of my mileage is urban commute and I tend to anticipate and avoid the need to brake more than most – but then I make up for it with a tendency to be heavy with the right foot on both pedals at times.

Given that sort of driving, is this the time to expect having to change pads?

The pads were first changed from the originals at 20000, but I only had the car for 6000 of those miles, so can’t really use that as a fair comparison.

• Typically, how many changes of pads will it be before the discs need changing?
  

cheers

Edited 18 July, 201213 yr by sidewaze samm

Pad warning is embedded in the pad liner, it is simply a short circuit that gets worn out when exposed, turning to open circuit and producing the warning. If it says change pads, you do need to change pads, though usually another 1k miles is no problem.

I do not remember wear limit, but it is not to the metal, probably 3-4mm of friction material must be left. I did 35k on my pads, though quite different driving, some traffic jams and a lot of high speed motorway with occassional emergency braking.

Re discs change, I have a policy of changing discs every 2nd pad change, but then I use very hard, kevlar based pads, so they do eat discs quite fast. I suspect you can get away with up to 4 "regular", soft pad sets before discs genuinely need replacement. If braking is even and not juddery, and the discs are within wear limit, then it makes no sense to change them.

Get Haynes manual for a Passat to get all wear limits/torque settings etc. (unless there's one for Mk1 Superb?)

If you plan to install pads without warning sensors (many otherwise good aftermarket pads do not have sensors), keep the cables from existing pads, short circuit each and plug into sensor sockets, tie loose ends away from brake, under sensor cables..

Rear pads often wear out quicker than fronts anyway and have no warning, so the front pad warning does not remove need for inspection.

When phoning up, I've now been told by the garage that - as they noted the pads as 30% worn 2000 miles ago - its probably the wire to a sensor that's worn through and shorting out, causing a spurious fault. Apparently a pretty common fault they say (though I don't think I've seen it mentioned on this forum...).

Personally I think this is BS and that in fact the pads are probably worn out after 33000 miles and their estimation of pad life was somewhat optimistic,(the rears were quoted as being only 20% worn, but also changed 33000 miles ago). :S Maybe it is a wiring fault and Tarox pads last a while. Maybe not.

Which brings me back to a question - if the sensors are working correctly and pad life is very low, is there an action that triggers the fault appearing? I presumed this would be when the brakes were actually used - possibly every time they were used. But my warning comes up inconsistently - sometimes after a couple of miles of driving (and braking), and sometimes as soon as I pull away, but only a couple of times coinciding with actually using the brakes. So could it be something other than low pads? Regretfully, I know nothing about the dirty side of brakes so wouldn't have a clue what I was looking at...

Need to take it in for a look-see, so any advice most welcome

cheers

Edited 19 July, 201213 yr by sidewaze samm

My pad warning wire has shorted the way the garage described on a couple of cars that I've owned, its not uncommon, might be worth you taking a wheel off and checking yourself.

Sent from my Galaxy S2 not a Crapple!

My pad warning wire has shorted the way the garage described on a couple of cars that I've owned, its not uncommon, might be worth you taking a wheel off and checking yourself.

So what's a likely price for this to be done? (no doubt they'll want to replace both sides!)

Cost me nowt just abit of electrical tape, its the wires that go from the pad to the plug on the car

Sent from my Galaxy S2 not a Crapple!

Cost me nowt just abit of electrical tape, its the wires that go from the pad to the plug on the car

Sent from my Galaxy S2 not a Crapple!

What was the wire shorted out to to give you the pad warning?

The way i understood this circuit, the wires are normally shorted; and when they go open circuit that is when the warning shows. The way people override the sensors permanently is to short them out at the connector plug.

So... I popped back with the car for them to check out whether it's the pads or the sensor wire. As expected, it's the pads. As for telling me just 1200 miles ago that they were only 30% worn, they said "there's plenty on the outer pads, it's the inner pads that are worn down".

Now forgive my ignorance (I really do wish I knew more about some things!) but I would have assumed each pad in a pair would wear fairly equally.

Is the sort of wear differential here normal and acceptable, or an indication something is not right with the way the brakes are set up, or disc wear etc? :S

I refuse to use a SUK dealer, and thought I'd have more success with a VW dealer where they've seen plenty of Superbs in the guise of Passats - and who are cheaper too - but obviously I was wrong. In addition to telling me the amount of life left in my pads based on the appearance of the outer pads only, yesterday they told me that the rear pads (that had previously been deemed to be 20% worn - presumably assessed on the same basis as the state of the front pads had been) were a little better and would "last until Christmas"... muppets!

At least EBC green and yellow pads wear out fairly evenly on outside and inside, though green pad lining tends to crack and chip after a while. I think if you have soft pad material it would wear out more on the inside as cooling would be worse on the inside.

It is normal for rear pads to wear out faster than fronts if you put all on at the same time. Rear brakes bite more, to prevent submarining and excessive weight transfer, but also because the rear discs are smaller, more force is needed for the same braking power.

Now forgive my ignorance (I really do wish I knew more about some things!) but I would have assumed each pad in a pair would wear fairly equally.

Is the sort of wear differential here normal and acceptable, or an indication something is not right with the way the brakes are set up, or disc wear etc? :S

In theory yes, pads should wear equally. However it doesn't take much crud on a calliper carrier or guide pins to stop a calliper (or brake pad) moving freely. Once this starts, it can change the way the calliper compresses the pads on to the disc, which, over time will cause uneven pad wear (and therefore braking efficiency). Add to the mix minor variations in pad material, or adjustable calliper angles and there ya go. I've seen on my own cars the inboard pad having greater wear than the piston side pad, which has often had me pondering as I'd have thought if a calliper's not moving freely, then it'd be the piston side pad getting pushed (and worn) more, but then again I come from an era when pads had lashings of asbestos in them and discs lasted a lifetime, so what do I know!Gaz

cheers guys - removes most of my concern. Just need to, pretty quickly, figure out what to get and where to go now. I've had no complaints in 33000 miles of Tarox pads, so might use them again if the price is still good. But it's three years since the fluid was changed, so maybe upgrade the fluid and get some of those EBC yellows.

EBC all the way..

The inner pad normally wears quicker, hence it being the one with the sensor in it. This happens as when the brakes are applied the piston moves which icing the inner pad this then touches the disc which pulls the caliper across and pulls the other pad in.