Can't get brake pad wear sensor code to shut off

chatcher · 12-22-2013, 06:27 PM

I did the front brakes on my 06 330i with oem parts replacing the wear sensor with a new unit. It has been a month or so now and the car is still throwing the code no matter how many times I try to erase it ( I use Bavarian technic for this). My m3 has brembos that I installed my self I bypassed the wear sensors on it so I decided to try that on the 330 to no avail. Thought it may be a prob with the brand new sensor ( it wouldn't be the first time I got a broken part out of a brand new box) but jumping the switch didn't shut the code off. Am I doing something wrong? Thanks in advance for any help

AtlantaDude · 12-26-2013, 11:59 AM

Did you reset the brake system through the car when you installed the brakes??

avocet · 12-26-2013, 12:24 PM

I just went through a similar issue...

the brake warning would not go away and the brake wear mileage indicator would not reset correctly. I am not sure but when I was trying to get it to reset I am pretty sure I tried to reset both front and rear mileage indicators. so now it read "-----" for mileage remaining on both front and rear, and resetting would not change anything.

I ended up having to do the rear as well... I actually just cut the wire, twisted them together and shrink wrap it at the right rear wheel. as soon as I did this, the system allowed a full reset and now indicates maximum mileage for pad wear(110000km I think...).

anyways, good luck. it was kind of a pain in the ass to deal with. I change over to winter tires, so am looking at brake wear closely at least twice a year. and I never trust electronic indicators... I still check tire pressures manually at least once a month.

and I hate bmw for ditching an oil dipstick...

Sparkee · 12-28-2013, 09:00 AM

I also have been through the same issue. Because I sometimes track the car and change pads a lot, I run my car with the sensors zip-tied to the suspension. I did a lot of research on this issue and found this information, which I believe is the same for the E90:

https://wiki.bentleypublishers.com/d...W+5+Series+E60

The brake pad wear sensors have a two stage resistance to them. When they have not been worn, they read 470 ohms. When the first wear point is reached, a bar is cut and they drop to 5 ohms. When a second bar is cut they drop to zero ohms (open).

So the DME expects to see 470 ohms of resistance across those wear sensors. Open reads an error - I know that is true. Shorted probably does too but I have not tried that and may be the case here.

I can verify that in at least some circumstances (like the circuit is open) the Condition Based Service (CBS) goes to an invalid % remaining, and the BT tool will not be able to reset the remaining wear because the DME refuses to accept the command (it says error still present). This may be true for any state other than the resistance being 470 ohms, but I cannot attest to that.

By the way, I filed down an old wear sensor that had broken leads and could see the bars. Inquiring minds sometimes have to know.

chatcher, my guess is the the pins in the wiring connector for the sensor are not making proper contact. Those pins are easily bent and in some cases a pain to get lined up. Bad connector design IMO. Shorting the connection probably doesn't work either - but as I wrote above that is a guess.

12-22-2013, 06:27 PM	#1
chatcher Private 101 Rep 73 Posts Drives: C6 ZR1 and E92 Join Date: Feb 2012 Location: butler pa iTrader: (2)	Can't get brake pad wear sensor code to shut off I did the front brakes on my 06 330i with oem parts replacing the wear sensor with a new unit. It has been a month or so now and the car is still throwing the code no matter how many times I try to erase it ( I use Bavarian technic for this). My m3 has brembos that I installed my self I bypassed the wear sensors on it so I decided to try that on the 330 to no avail. Thought it may be a prob with the brand new sensor ( it wouldn't be the first time I got a broken part out of a brand new box) but jumping the switch didn't shut the code off. Am I doing something wrong? Thanks in advance for any help
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12-26-2013, 11:59 AM	#2
AtlantaDude Just enjoying my time 128 Rep 855 Posts Drives: 2007 BMW E92 335i - Sold Join Date: Mar 2012 Location: Atlanta iTrader: (0)	Did you reset the brake system through the car when you installed the brakes?? __________________ Current - 2022 Rivian R1T, 2021 Ducati Streetfighter V4S, 1969 Chevy C10 Sold - 2018 Tesla Model 3 Performance Sold - 2007 E92 335i If speed is death, then buy a Honda and live forever
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12-26-2013, 12:24 PM	#3
avocet Major 252 Rep 1,157 Posts Drives: 2007 328i 2011 X5d Join Date: Sep 2010 Location: Vancouver bc iTrader: (0)	I just went through a similar issue... the brake warning would not go away and the brake wear mileage indicator would not reset correctly. I am not sure but when I was trying to get it to reset I am pretty sure I tried to reset both front and rear mileage indicators. so now it read "-----" for mileage remaining on both front and rear, and resetting would not change anything. I ended up having to do the rear as well... I actually just cut the wire, twisted them together and shrink wrap it at the right rear wheel. as soon as I did this, the system allowed a full reset and now indicates maximum mileage for pad wear(110000km I think...). anyways, good luck. it was kind of a pain in the ass to deal with. I change over to winter tires, so am looking at brake wear closely at least twice a year. and I never trust electronic indicators... I still check tire pressures manually at least once a month. and I hate bmw for ditching an oil dipstick...
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12-28-2013, 09:00 AM	#4
Sparkee Stability is Overrated 6 Rep 66 Posts Drives: '08 E90 328i Sedan w/MT6 Join Date: Nov 2011 Location: MD iTrader: (0)	I also have been through the same issue. Because I sometimes track the car and change pads a lot, I run my car with the sensors zip-tied to the suspension. I did a lot of research on this issue and found this information, which I believe is the same for the E90: https://wiki.bentleypublishers.com/d...W+5+Series+E60 The brake pad wear sensors have a two stage resistance to them. When they have not been worn, they read 470 ohms. When the first wear point is reached, a bar is cut and they drop to 5 ohms. When a second bar is cut they drop to zero ohms (open). So the DME expects to see 470 ohms of resistance across those wear sensors. Open reads an error - I know that is true. Shorted probably does too but I have not tried that and may be the case here. I can verify that in at least some circumstances (like the circuit is open) the Condition Based Service (CBS) goes to an invalid % remaining, and the BT tool will not be able to reset the remaining wear because the DME refuses to accept the command (it says error still present). This may be true for any state other than the resistance being 470 ohms, but I cannot attest to that. By the way, I filed down an old wear sensor that had broken leads and could see the bars. Inquiring minds sometimes have to know. chatcher, my guess is the the pins in the wiring connector for the sensor are not making proper contact. Those pins are easily bent and in some cases a pain to get lined up. Bad connector design IMO. Shorting the connection probably doesn't work either - but as I wrote above that is a guess.
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