Allen

So I'm going through the RESET procedure for the oil light...which I have done many times with no problems...and the oil light resets no problem. But when the "reset menu" goes away (after not touching anything for like 5 seconds)...the Front Brake pad light comes ON red. So I go in to reset it, and it won't reset...it shows "-9000 miles" remaining on pads. Now my car does have 88,000 highway miles and the pads will need changing soon...but looking at the pads...they have easily another 20,000 left.

I know about the wear sensor, how to measure it for resistance and all that...but the circumstances almost surely indicate some software "glitch". Anybody ever seen this?

tonyb635

I've never actually tried resting this without a new sensor. I wonder if it has something to do with using the old sensor in the reset process?

twh

I think that the brake pad dash indicator will not reset if the sensor has worn though at the brake pad.

Allen

I believe this to be true. But the sensor could not have all of a sudden "wore through" when I was resetting the oil light. It was perfectly fine before I started the procedure to reset my oil light.

I'm pretty sure it is related to the sensor. Maybe anytime a light (oil, brake fluid, brake pad, etc.) is reset...the system takes a "special" reading of the pad sensor resistance..."special" meaning the tolerance is much tighter. Just a guess, but it's gotta be something like that.

Thank you guys for the response

Allen

My front pads appear to have about 20,000 left on them. Since I will be getting a new pretty soon anyway...I may just take this sensor cut & tie the leads together. I bet my light will clear then. Then just monitor the brakes the "old fashion way"...wait for them to squeal.

The big question then is...do the OEM pads have "Squeal Tabs". I'm sure they do...even if not...it's very easy to see the pads through the wheel.

tonyb635

I don't know for sure, it's on a feeling. Recently, I turned my rotors and cleaned up the pads. They had tons of material left. I did not reset because I was thinking this might happen. When the count down starts, I think at that time I'll just replace the sensor and pads together. You could always just through a new sensor on there. I don't think I would let it go for a long time in the negative though because I also heard that at some point the reset may not work and you have to reset it with external software. Again, these are just things I remember reading here and there on forums.

Allen

I thought about that...but when I mount the new sensor...it will certainly instantly wear down to the point that the current sensor is...which is apparently a problem. As far as the car/system is concerned...shorting the existing sensor would be the same as a new sensor.

twh

It is strange that it all happened when you fussed with the reset. I think the sensor is two stages of resistance depending on how much has been scraped away.

Allen

It is indeed strange...the reset procedure is really easy, and I've done it many times with no issue. How could the sensor just all of a sudden "change"...??? ....quite puzzling.

You are correct on the 2 stages...here is a good article on the sensor....note that a new sensor has < 5 ohms resistance...thus allowing you to tie the leads together (0 ohms) to "make the sensor appear new to the car/system".

https://wiki.bentleypublishers.com/display/tech/Brake+pad+wear+sensor+testing+BMW+5+Series+E60

AutohausAZ-Mike

As far as what I am familiar is that the brake pad wear sensor light cannot be reset unless the sensor is replaced. The sensor is activated when the circuit breaks, which triggers the warning on the dash.

It seems like it will be more of a headache to try to fix the sensor other than just to replace it. The sensors usually go between 10-15 dollars for some of the E60 models.

Take a look at our website to get the exact cost of the part for your vehicle.