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ryhi
12-25-2003, 03:15 PM
its the light next to the "bulb out" light...and it looks like this (O)

i dont have the manual...so i duno what it is. last night i replaced my maf sensor...but i duno if this has anything to do with it....it was on for a short time..its already off, but i just want to know what it is.

KenzBenz
12-25-2003, 04:04 PM
whens the last time you changed your brake pads? im just gussing because the brake pad low light sorta looks like "(O)" is it on the left side or right side in the cluster?

hvmercy
12-25-2003, 06:03 PM
Originally posted by ryhi
its the light next to the "bulb out" light...and it looks like this (O)

i dont have the manual...so i duno what it is. last night i replaced my maf sensor...but i duno if this has anything to do with it....it was on for a short time..its already off, but i just want to know what it is.

It's the "brake" warning light. Mine came on and I took it in to the shop. You should have it checked.
hvmercy

ryhi
12-26-2003, 09:47 AM
i changed my rears like 2 months ago, and my front onews were still pretty good...could rain have any part on this? it turned on for like 1 minute, then turned back off..

Denlasoul
12-26-2003, 12:54 PM
When power from your battery (not fully charging) starts to fade, that light comes on as an indicator. Also comes on when you disconnect your battery for a period of time.

I'd check the voltage on the battery to make sure this is not causing the indicator to light up.

nokia8860
12-26-2003, 02:24 PM
Aftermarket pads have a negative effect on the sensor itself causing it to go bad fairly quickly. So unless you are using OEM pads its best not even to install these sensors.

sph17
12-30-2003, 03:53 PM
If the sensor to the brake pad is old/worn/cracked it can allow the circuit to be completed when it is wet outside and water gets into the wire that is the sensor.

On the other hand, your pads may be worn, or the "lip" on the outer edge of your rotor (if you have old rotors that have seen two or three sets of pads without being replaced) may have worn into the sensor at the top of the pad, even though the rest of the pad looks good.

ryhi
12-31-2003, 09:23 AM
thanks for all the info guys

KenzBenz
12-31-2003, 09:48 AM
[i]
On the other hand, your pads may be worn, or the "lip" on the outer edge of your rotor (if you have old rotors that have seen two or three sets of pads without being replaced) may have worn into the sensor at the top of the pad, even though the rest of the pad looks good. [/B]

is it dangerous if the lip on the outer edge of the rotor is a little worn??

sph17
12-31-2003, 11:18 AM
Originally posted by KenzBenz
is it dangerous if the lip on the outer edge of the rotor is a little worn??

Disclaimer: I am not a Mecanic. I have/had 6 MB's and I changed my own pads and rotors through +700K miles.

I have found that the MB pads don't go to the edge of the rotor, so the last 1/4 inch (3mm fo you metric fans) of rotor dosn't get worn. As the pads wear down the rest of the rotor, this "lip" of almost original thickness rotor remains. If you have your rotors "turned" at a brake shop, they shave this lip off, when they true it up the rotor on the lathe. MB dosn't reccomend turning rotors as they are made of relatively soft metal, and they are relativly cheap, so the reccomendation is if they are below a certain thinkness, replace them. The reccomendation for my W123 rotors are either 9mm or 7mm thickness for replacement. If you don't have a set of callipers to measure, you can use an open end metric wrench, but you need to file off the 'lip' in a small area to slip the wrench onto the rotor to measure the 'true' thickness.

Though my +700k miles, I have tried to file down the lip, I have used an old screwdriver as a "lathe" cutter and turned the rotor under the screwdriver using the caliper as a rest to try and "cut" off the "lip" or at least make it thinner. I finally just gave up and just try to get the rusted mental at the edge of the rotor off when I change my pads.

My only problem has been is when I have had an old rotor, at the end of its life, with an old set of pads that need to be replaced, and the combination almost allowed the brake piston to push the brake pad metal plate to touch the center retaining metal spring on my W123s, but that didn't have any thing to do with the "lip". The only problem with a big lip, is as I mentioned, it will cut into the sensor early, causing you to replace the pads a bit early.

Happy New Year!!

<sph17>