I have the yellow warning light illuminated on my dashboard, the manual states that this light means barke pads are worn to excess, all pads appear to have plenty of life in them.
Where are the sensors for the pads?
first off check brake fluid level as the same light often does both jobs, the worn pad sensors are in the pads themselves, so a strip of each brake assembly is next after the brake fluid check
Brake fluid is a different light, There are no wires for/or connected to front calipers, haven't checked the rear.
it would be unusual to have sensors on the rear but not the front.
has this just occurred, or been like it for a long time? perhaps the sensors are missing from the front pads which would also cause the light to be on
No this light has only just come on, Im wondering if this model does not carry brake pad warning sensors, suppose the dashboard is standard throughout the range, the light being on could a systems management fault.
In the pads themselves. When the pads wear down a certain amount the electric circuit is broken and the light goes on. If the friction material on the pads (and not just the pads themselves) look OK, look instead for a poor connection on the wiring coming from the pad(s).
There are no wires or connections, that's why it's a mystery
No, there's only a single wire to pads normally. When the pad wears, it's earthed against the disk.
If cheap pads have been fitted in the past, without wear sensors, the wires to them may have been tied out the way somewhere - or even snipped off - and are now earthing where they shouldn't.
There are only two - one for the back and one for the front. They are clipped into one of the pads on that caliper - obvious by the wires going to it.
If the wiring is damaged or the sensor unplugged the warning light will come on. They also need replacing at pad change time if the warning light has come on.
Deoends on the car, the last ones I played with came on if the wire earthed or broke so you had to bypass the connection rather than remove it.
Not on BMWs. They use a continous loop system the same as Iveco and VW.
Every chance the sensors havn't been fitted (you've got to buy them seperate from the pads for BMWs), and instead, they've just been cut and joined together at some point, and the connection has now corroded.
The BMW sensor - and others using the same brakes - is actually a loop covered in plastic. The plastic wears through when the pads get too thin and the loop earths latching on the warning light. Or if the loop (continuity) is broken in another way.
BMW sensors are a separate item costing about a fiver each. If you change the pads before the light comes on you *may* be able to re-use them - but they can break when removing from the pad.
To reset the latch after changing the sensor you need to switch on the ignition without starting the engine and wait a couple of minutes till the light goes out.
moray ("moray" ) gurgled happily, sounding much like they were saying:
Ah. Not come across that.
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