Brake Pads Warning Light Illuminated

[ben_aip]

Need some help or advise from fellow forum members: I had my 40000km (25k miles) service done 2 weeks ago on my 2010 Q5. Brake pads reported to be 5mm front & 7mm rear, remaining. Service adviser said the front should be good for another 3000 to 4000km. I placed an online order last week for Centric Posi-Quiet and Power-Slotted Rotors last week, but won't be here till another 7 to 10 days (customs clearance, etc). Brake pads warning light came on last night, barely 1000 km after that service report. I need to travel over the Rockies on Wed for a business trip to Alberta(>2500km to & fro). Questions: - When that pad worn light shows, APPROX how far can one continue driving safely before pads replacement? (I know depending on one's driving and terrain), but how much 'meat' are normally left on OEM pads, upon light on? - Could it be a false warning, as I'm not expecting this to occur till maybe another 2000 to 3000 km from 5mm thickness, unless it was not measured right at service 2 weeks ago. - Understanding my dilemma - must drive situation + new pads and rotors on it way in; am I crazy to want to take the risk and make this trip first then fix it when I'm back in town. Thanks one and all.

[Just Me]

its not very precise. The sensor is nothing more than a wire embedded in the pad. when it makes contact with the rotor, or cuts through, the light goes on.

Typically you have 2+mm of pad material left, which is a lot, really.

of course, switchbacks through the Rockies might be challenging. Why not take the wheel off and look for yourself?

bear in mind a new pad is about ~10mm pad material,plus backing plat of around 3-4mm. Did that 5-7 include the backing plate? Its only a 300% difference :-)

G

[john_taps]

The answer of your first question is that the car run about only 900 miles maximum, the second ting there is only false lighting when you got your sensor out of order, to check whether the light is ok or not just measure the thickness of the pad that is 5 mm maximum. So I suggest you to do not take the risk as these are your business trip...

[john_taps]

The answer of your first question is that the car run about only 900 miles maximum, the second ting there is only false lighting when you got your sensor out of order, to check whether the light is ok or not just measure the thickness of the pad that is 5 mm maximum. So I suggest you to do not take the risk as these are your business trip...

[Just Me]

Where do you get your numbers from? 900 miles?

what assumption are you making about pad vs backing plate?

I don't see how you can assert what you are asserting.

G

[ben_aip]

Thanks for your inputs guys.
I did get the front brake pads looked at before I left for the trip.
Was told by a couple of independent mechanics that it should be safe to go.
On some of those long mountain downhill passes I used a combination of engine and brakes to slow down when I need to.
Just got back - all good. The Q5 (3.2li) drives like a dream! Lots of power, very stable, and quiet at speeds up to 150 kph to momentarily 180 kph.
Cruising at 120 - 130kph returned a manually calculated consumption of 30 to 32 mpg(UK).
My Centric Posi-Quiet Pads and Power-Slot Rotors had also just arrived. Going to get all four corners fixed tomorrow. Should eliminate at least 80% to 90% of brake dust problem, as experienced by fellow forum members using the same setups.