E38 Check brake linings/brake light message

I have replaced the front brake pads on my 98 740il and the brake lining
message and brake light is still on. Do they have to be reset this or will
they automatically go off when the condition is fixed?

"RCG52" > wrote in message
...
>I have replaced the front brake pads on my 98 740il and the brake lining
> message and brake light is still on. Do they have to be reset this or
> will
> they automatically go off when the condition is fixed?
>
>

Did you replace the sensor or forget to plug it back in when you replaced
the pads? There's one on the front driver's side (left) and one on the rear
right.

Kyle.
98 740iL
97 M3

There is a sensor that must be replaced.

In simple terms, the sensor looks much like a fuse. As the brake pads wear,
the sensor comes in contact with the rotors and breaks, a new sensor has to
be installed to repair the break.



"RCG52" > wrote in message
...
> I have replaced the front brake pads on my 98 740il and the brake lining
> message and brake light is still on. Do they have to be reset this or
will
> they automatically go off when the condition is fixed?
>
>

I did not replace the sensor with a new one and I chipped a piece of the
backside off while removing it. So when replaced, it will turn off the
check message and brake light?

"Kyle and Lori Greene" > wrote in message
...
>
> "RCG52" > wrote in message
> ...
> >I have replaced the front brake pads on my 98 740il and the brake lining
> > message and brake light is still on. Do they have to be reset this or
> > will
> > they automatically go off when the condition is fixed?
> >
> >
>
> Did you replace the sensor or forget to plug it back in when you replaced
> the pads? There's one on the front driver's side (left) and one on the
rear
> right.
>
> Kyle.
> 98 740iL
> 97 M3
>
>

Thanks.

"Jeff Strickland" > wrote in message
...
> There is a sensor that must be replaced.
>
> In simple terms, the sensor looks much like a fuse. As the brake pads
wear,
> the sensor comes in contact with the rotors and breaks, a new sensor has
to
> be installed to repair the break.
>
>
>
> "RCG52" > wrote in message
> ...
> > I have replaced the front brake pads on my 98 740il and the brake lining
> > message and brake light is still on. Do they have to be reset this or
> will
> > they automatically go off when the condition is fixed?
> >
> >
>
>

There are, in fact, 2 sensors driver front brakes and passenger rear brakes
(or vis versa). Always replace the sensor(s) when you do a pad change, one
or both depending on which set you replace.


"RCG52" > wrote in message
...
> Thanks.
>
> "Jeff Strickland" > wrote in message
> ...
>> There is a sensor that must be replaced.
>>
>> In simple terms, the sensor looks much like a fuse. As the brake pads
> wear,
>> the sensor comes in contact with the rotors and breaks, a new sensor has
> to
>> be installed to repair the break.
>>
>>
>>
>> "RCG52" > wrote in message
>> ...
>> > I have replaced the front brake pads on my 98 740il and the brake
>> > lining
>> > message and brake light is still on. Do they have to be reset this or
>> will
>> > they automatically go off when the condition is fixed?
>> >
>> >
>>
>>
>
>

If you look at the part closely, you will find that there is a very thin
band of metal that goes across the face (side towards the rotor). Yours will
not have the metal band, or if you got to it early enough you might see it
broken.

As the pads wear down, the band touches the rotor and this turns the light
on. The band eventually breaks. If you get into the habit of looking at the
brake pads while washing your car, you can usually see if the pads are
nearing end-life. If you manage to replace the pads before the warning light
comes on then you can avoid buying new sensors.

The warning light does not differentiate between front and rear brakes, so
there could be two sensors broken or the sensor you look at first is not the
broken one. The sensors are on diagonal tires, front left and right rear if
I remember right.




"RCG52" > wrote in message
...
> I did not replace the sensor with a new one and I chipped a piece of the
> backside off while removing it. So when replaced, it will turn off the
> check message and brake light?
>
> "Kyle and Lori Greene" > wrote in message
> ...
> >
> > "RCG52" > wrote in message
> > ...
> > >I have replaced the front brake pads on my 98 740il and the brake
lining
> > > message and brake light is still on. Do they have to be reset this or
> > > will
> > > they automatically go off when the condition is fixed?
> > >
> > >
> >
> > Did you replace the sensor or forget to plug it back in when you
replaced
> > the pads? There's one on the front driver's side (left) and one on the
> rear
> > right.
> >
> > Kyle.
> > 98 740iL
> > 97 M3
> >
> >
>
>

In article >,
RCG52 > wrote:
> I did not replace the sensor with a new one and I chipped a piece of the
> backside off while removing it. So when replaced, it will turn off the
> check message and brake light?

If it's like the E39, just replacing the sensors won't turn off the
warning immediately. You have to turn on the ignition without starting the
engine for a couple of minutes. Or it will just happen after a few days
normal driving.

--
*I don't suffer from insanity; I enjoy every minute of it.

Dave Plowman London SW
To e-mail, change noise into sound.

In article >,
Jeff Strickland > wrote:
> If you manage to replace the pads before the warning light
> comes on then you can avoid buying new sensors.

You might. However, the plastic becomes very brittle with the heat, and it
may just break up on removal - even if unworn. Don't ask how I know. ;-)

--
*Generally speaking, you aren't learning much if your lips are moving.*

Dave Plowman London SW
To e-mail, change noise into sound.

"Jeff Strickland" > wrote in message
...
> If you look at the part closely, you will find that there is a very thin
> band of metal that goes across the face (side towards the rotor). Yours
will
> not have the metal band, or if you got to it early enough you might see it
> broken.
>
> As the pads wear down, the band touches the rotor and this turns the light
> on. The band eventually breaks. If you get into the habit of looking at
the
> brake pads while washing your car, you can usually see if the pads are
> nearing end-life. If you manage to replace the pads before the warning
light
> comes on then you can avoid buying new sensors.
>

However, if you are one who religiously checks the break pads whenever you
wash your wheels, then you can get a lot more distance on the pads before
replacing them - especially on the lightly stressed rear brakes.

My wife put nearly 30,000 km on her E36 from the time the rear brake sensor
turned the check brake disks light on, until I had to replace the pads and
sensor to get the car through the annual registration inspection. Still a
safe amount of pad left before hitting metal when I replaced them.

The front sensor went on my E34 shortly before the annual inspection was
due, so I pulled the sensor, clipped the wire and twisted both wires
together to close the circuit. It took a day or two before the ECU turned
the dash light off. With no warning lights alight the car passed the
inspection. About six-months later I decided to replace the pads and sensor
in preparation for a holiday trip. Once again, still a safe amount of pad
left.

But if you don't visually keep a check on your pads regularly, by all menas,
get the dealer to whack in new brakes as soon as practical after the light
goes on. For the DIY guys like me, a new brake sensor costs about $5 for the
E34 and $14 for the E36. And where I live the front sensor is in the
passenger side brake, the back in the drivers side rear brake pad. Same brak
e pad as anywhere else, but we put the driver's seat on the right hand side
of the gear shifter.

Bill K.