Just had my first service at 22k miles and the system is telling me my front brakes need servicing in 4,000 miles and the rear in 9,000 miles. What is it basing this on and how accurate is it? As I am 120 miles from the dealer I am planning to go back in 9k miles and get both done and the front pads don't look that bad.

 

Usually the brake wear light's based on the wear indicators that clip into the pads. if the pads look good it's possible you either have uneven pad wear (inside's more worn down then the outside) or something might've been left disconnected after the service work.

The mileage is probably a guess/calculation based on how far they think you can make it with 1/4 pad left (or however little it might be), but that numbers from the same OBC that recommends 18k between oil changes.
Someone's going to get seriously hurt after letting their brakes go the 4-9k miles after getting that msg, all to save BMW some money on their 'free maintenance'.

 

let me ask this another way.

We know that on the GEN1's that have wear sensors, the lite comes on when the pad wears down and the end of the sensor is physically ground off by the rotor. If the sensor works as designed, a fairly GOOD indication that the pad is worn.

But what is the number on the GEN2 derived from? Is it a pure count down? Or is there some alleged analysis as in the oil change/basic service counter?

Anyone? Beuller?

I had a dealer try to sell me pads on my GEN1 based purely on my miles driven. Shame he didn't actually LOOK at the pads which were a month old kinda destroying his credability.....

Eyeball the pads when you rotate the tires .... an easy check. When the pad material is thinner than the backing plate - change 'em

 

well the 2nd gen pads also have sensors, the warning should trigger at 3mm, maybe just call the dealership & ask what it means ?

 

Listen Nothing is left off nothin is wrong. Its called CBS condition based service. It uses a Algorithm formula on your driving style. Its kind of like maint countdown. Trust me it knows when you will need pads. I service Mini and BMWs this is how the system works. you have nothing to be alarmed about. don't even try to analyze how it works. But it does.
The 1 Gne mini is is gorund sensor soon as it grounds against metal it trips the light.

Hope this helps.






Guido

 

I still don't get how this works - what is the algorithm basing its calculation on. We could have two drivers with different driving styles - one always uses the brakes to slow down, the other downshifts and uses engine braking so rarely touches the brakes. How does the algorithm know that the first needs the pads changed much sooner than the second?

Also, is there still a wear sensor telling me that the brakes have actually reached a limit. If so, I can use the predicted life of the pads as a guide on when to expect the sensor to warn me but not do anything until I am told the pads really need changing. Of course, who needs a sensor if you actually take a look at the pads!

 

I don't know what the OBC does do on a MINI, but I can see how it could calculate brake useage by correlating the time brakes were applied with the change in speed while braking. This would be fairly easy to program if one had data on brake wear per mph of speed decrease. It could be modified by the rate of deceleration.

 

To do it right it could look at the engine speed and throttle to see if there is engine braking but this is getting complex. More likely it takes a conservative approach and ends up replacing some pads sooner than needed.

The computer is telling me the front pads need replacing at 26k miles which is about half the 48k miles it took to replace the pads on my 2002 MCS and I drove both cars the same.

 

I am at 26 k KM and it is telling me to change my brakes

my brakes in my 2003 mini went 60 k KM before a change

I am skeptical.

I had my brakes checked at a Fountain Tire shop and they told me that I have tonnes of brakes left

he gave me a weird measurement something like 7/32

does anyone know what this means.

 

That's seven thirtyseconds of an inch, or a small amount under a quarter of an inch. One thirtysecond of an inch is half of one sixteenth of an inch.

For brakes, that means there's plenty of life left in your pads.

 

And I'll bet that algroythm isn't going to be able to correctly project the end of life on other brands of pads. Since EBC Green is supposed to be pretty close wear wise, it'd probably be pretty close. If you're using one of the other EBCs (Red, Yellow, etc.), lots of miscalculation there. Now we're going to have one more thing to modify - a brake wear chip mod?

 

Hey guys,

I've got a 2004 MCS and last night I replaced the pads and rotors on the rear because the brake wear indicator lit up. I've put 64K miles on the rears (dealer replaced fronts 6 months ago). By the way, the stock pads looked like they had at least half the of pad remaining.

Anyway, after replacing the pads, and the sensor, I got in the car for a quick test drive and I noticed that the dash brake wear indicator was still lit. How do you reset this indicator ? I would have thought that it would have gone out as soon as a new sensor was connected.

Any help would be appreciated.

E-

EDIT: I just realized that I posted this in the wrong forum. I'll repost in the right one, but if anyone has a solution, please feel free to offer.

 

This is what I think is happening. I think the MINI OBC just estimates the brake pad wear and at a certain mileage, tells the owner to take the car in for an inspection. Based on a physical inspection, the dealer will decide whether the pads need changing or not. It's just a reminder system. There is no way a computer or human can predict with certainty how many more miles are left on the pads because nobody can know with certainty how the car will be driven in the future.

But there is also a brake wear sensor in some/all of the brake pads that will trigger a dash warning light when the pads are actually physically worn down. Probably around 2-3 mm (1/8") or so of pad left. The sensor is just a wire that is stuck inside the pad and when the pad wears down enough to break the wire, the warning light illuminates.

It's pretty easy to just take a light and eyeball the pads for wear. It's probably not a good idea to let the pads wear down to less than 2 mm.

IIRC brake pads are covered under the service maintenance plan.

 

To reset the light Just disconnect the battery for about 10 seconds.

 

I have also got a problem with this damn warning light after changing pads. New pads are in, everything is connected, car has been driven and the brakes are good but the light is still on.

I tried disconnecting the battery for 10 minutes (and losing all trip memory ) but it is still on. I am guessing it is a take it to BMW and get taken for a ride situation. Does anyone have any ideas?

 

Assuming you replaced the sensor and it is properly connected, turn the key to position 2 for about 30 seconds without turning the engine over...

From MiniMania's listing for the sensor

others have said this works.

edit: oops, my bad, this IS the GEN2 forum.....no key. But an answer is below...thanks.

 

Sorry, I forgot to mention I have a R56, no key to turn to position two, just a plug in electronic key

 

Insert your key fob, then start pushing the Start button with your foot OFF the brake (very important). The car won't start and you'll reach the equivalent of key position 2 on the second button push. This is also how you get access to most of the driver controllable option in the Setup mode of the car, like setting how/when the doors lock and unlock, how many turn indicator clicks you get, how the lights come on, resetting the TPS system, etc.

It's all in your owner's manual, but spread out over several sections.

IMHO as a mechanic of airplanes, if you're getting your car back from the shop after the brake warning light has come on, AND the light is still on, then the shop didn't complete the job you hired them to do. The first course of action for me would be to take it back to the shop, or, at the very least, call the shop as soon as you notice the brake light is on and get their opinion as to how to turn it off.

 

Thanks for your help on this, I will give it a try.

I could take it back but I changed the brake pads myself. After working in the automotive trade many years I am pretty handy with a spanner but this warning light is a whole new thing to me. Most aussie cars are pretty basic and don't have this electrotrickery.

 

Ain't that the truth! I don't know what it's like Down Under, but BMW-USA is being pretty stingy in allowing owners access to technical data for the Mini. All I know about the shop manual is that it comes on a series of disks, and that's third-hand information. Drives me nuts not knowing what's going on in my car.

My first exposure to computer-controlled vehicles was the Airbus A320 while working at Northwest Airlines about 15 years ago. I was working as a ramp rat and I would watch the mechanics spend 15 minutes to fix the physical problem, then 2 hours to clear the fault page from the plane's computer so it was legal to fly.

Anyway, good luck with the brakes.