brake wear warning light

Post Wed Mar 23, 2005 5:31 pm

afternoon all
a little while ago i replaced front disks & pads + sensor

but the pad wear light was still flickering and then suddenly went to permanent

so today i have replaced the rear disks & pads + sensor
and its still on

now my question is should the light go out straight away
or does it take a little while to settle itself

the light i am talking about is the one on the dash
hope you can help

thanks
Malcolm

Post Wed Mar 23, 2005 5:43 pm

You've got a bad connection somewhere. Could be at the sensors or the infamous dry/cracked solder joints inside the instrument cluster (search forum for "220" ohms?)

It's an instantaneous effect. The start of the loop is connected to +12 through a resistor, it goes through both pad sensors and back into the instruments.

There it's connected through an even bigger resistor to ground. This creates a potential divider.

If the voltage goes below a certain level (sensor grounding on disc or sensor opening and resistor pulling node to ground), the light comes on.

No memory, no time delay etc.

Post Wed Mar 23, 2005 11:00 pm

Before you get too involved with the cluster, check that the front pad sensor is still in place properly, and the wires havn't rubbed through on the inside of the wheel rim.

Post Thu Mar 24, 2005 1:45 am

ive got this light on in all my cars

Post Thu Mar 24, 2005 6:48 am

just take teh bulb out

Post Thu Mar 24, 2005 8:03 am

thats wot im gonna do

Post Thu Mar 24, 2005 9:26 am

I have the same issue - my one comes and go's, but the sensor have all been replaced with new. Only thing I can spot for sure is that it seems to happen more often in damp conditions

Post Thu Mar 24, 2005 10:14 am

If it's the pad wear light, (and it probably is), and you want to fix it properly rather than bodging it, take out the instrument cluster and open it up. Near the temperature gauge, you will see the connections to a large 220 ohm resistor. (Position corresponds to a rectangular lump on the back of the instrument cluster casing.) Resolder these two joints and all will be well.

this is courtesy of brian mooore ...on first page of this site someone should put it in technical help

Post Mon Mar 28, 2005 9:49 am

update on this
i changed my wheels on saturday to some BBS (thanks Andy)
and while i was doing it i checked the connectors
and made sure they were connected properly
and yesterday the light just seemed to go out
so no more red light on my dash yipeeeee
cheers for the help fellas