No brake-wear sensor on my E320 Bluetec - PeachParts Mercedes-Benz Forum

bhehmann · #1 12-08-2011, 12:24 AM

Good day.

I purchased a previously-owned 2008 E320 Bluetec a year ago. At the time it had done about 29,000 miles.

Yesterday we changed out the front brake-pads (just two days after the brake warning lit up on the instrument panel) and noticed that the pads were after-market and the left side had no sensor, nor did we see any wiring for a sensor.

Shouldn't this car have sensors on both front brakes?

Regards,

cessna5354 · #2 12-08-2011, 05:12 AM

With out casting dispersions, I would say the car certainly came with sensors, both sides. However, the car did not come with after market parts.
I do not know how you go thru two sets of pads in < 28K miles, but 90% of my driving is highway.

Best of luck with the BlueTec, I hope one is in my future.

tyl604 · #3 12-08-2011, 07:46 AM

As someone who still drives my 81 SD I would be interested to know if Mercedes still puts the sensor in the hole in the brake pad. It was a pretty good and fault free system. Let us know what you find out. And the old sensors are reusable sseveral times unless you drive a whole lot after the warning light comes on.

tangofox007 · #4 12-08-2011, 09:35 AM

Quote:

Originally Posted by cessna5354

I do not know how you go thru two sets of pads in < 28K miles, but 90% of my driving is highway.

Do you read while you drive?

Quote:

Originally Posted by bhehmann

I purchased a previously-owned 2008 E320 Bluetec a year ago. At the time it had done about 29,000 miles.

bhehmann · #5 12-08-2011, 06:04 PM

Quote:

Originally Posted by cessna5354

With out casting dispersions,

dispersions: plural of dis·per·sion (Noun): 1. The action or process of distributing things or people over a wide area. 2. The state of being dispersed over a wide area.

Quote:

Originally Posted by cessna5354

I would say the car certainly came with sensors, both sides.

Speculation?

Quote:

Originally Posted by cessna5354

However, the car did not come with after market parts.

Stating the obvious!

Quote:

Originally Posted by cessna5354

I do not know how you go thru two sets of pads in < 28K miles, but 90% of my driving is highway.

FYI, when I bought the car, it had 29000 miles on the clock, I drove it for another 10000 miles, therefore total mileage is now 39000!

I don't know how hard the previous owner drove the car, but the one set of pads was down to metal-on-metal.

Can't Know · #6 12-08-2011, 06:28 PM

MB started reducing the number of sensors on some models years ago. Some have only one front and one rear (with the theory being, I suppose, that the fronts will wear pretty much the same).

My car (base W210 sedan) has two front wheel sensors, and no rear wheel sensors. The backs wear so slowly that I'd guess they are just relying on the A&B inspections to pick those up. I've toyed with the idea of adding a rear wheel sensor, but considering I've got a bit over 80,000 miles on the rears -- still with some life left -- I can't really see it as a priority.

If you don't see a provision for connecting the sensor where it is "missing", then it's the way MB designed it. After all, you have one on the other side of the axle, so I'd tend to think you're good to go.

Good luck.

bhehmann · #7 12-08-2011, 06:35 PM

Quote:

Originally Posted by Can't Know

MB started reducing the number of sensors on some models years ago. Some have only one front and one rear (with the theory being, I suppose, that the fronts will wear pretty much the same).

My car (base W210 sedan) has two front wheel sensors, and no rear wheel sensors. The backs wear so slowly that I'd guess they are just relying on the A&B inspections to pick those up. I've toyed with the idea of adding a rear wheel sensor, but considering I've got a bit over 80,000 miles on the rears -- still with some life left -- I can't really see it as a priority.

If you don't see a provision for connecting the sensor where it is "missing", then it's the way MB designed it. After all, you have one on the other side of the axle, so I'd tend to think you're good to go.

Good luck.

Thanks for the reply. It makes sense in using only one sensor, provided the brakes wear evenly, however, mine didn't.

On the other hand, I've heard it said that there were earlier MB models that had two sensors at varying depths, therefore you would get two warning indications, in case you missed the first one. Any truth in that?

Regards,

Can't Know · #8 12-08-2011, 06:41 PM

Quote:

Originally Posted by bhehmann

Thanks for the reply. It makes sense in using only one sensor, provided the brakes wear evenly, however, mine didn't.

On the other hand, I've heard it said that there were earlier MB models that had two sensors at varying depths, therefore you would get two warning indications, in case you missed the first one. Any truth in that?

Regards,
Bjoern

I've never heard that about two sensors; I always heard that the second warning is that ugly crunching, grinding noise.

I'm interested in why yours would wear unevenly, though. Perhaps it's just the fact that they are cheap aftermarket pads with poor quality control so there is either a variation in compound or maybe even one pad was already worn. Lots of the cheapo aftermarket buys lots and then repackages, so I suppose it is possible you could end up with different compound pads on the same axle.

What brand did you replace them with?

bhehmann · #9 12-08-2011, 07:24 PM

Quote:

Originally Posted by Can't Know

I've never heard that about two sensors; I always heard that the second warning is that ugly crunching, grinding noise.

I'm interested in why yours would wear unevenly, though. Perhaps it's just the fact that they are cheap aftermarket pads with poor quality control so there is either a variation in compound or maybe even one pad was already worn. Lots of the cheapo aftermarket buys lots and then repackages, so I suppose it is possible you could end up with different compound pads on the same axle.

What brand did you replace them with?

That makes sense, thanks. I replaced them with pads from the MB dealership.