Brake replacement

[Guest]

When I replace my brake pads and discs (F&R), do I need to replace the sensors too?

Okay, another daft question, but I am a girlie after all (and trying to learn fast!)[]

 

[Sean Dunne]

Not sure about the Boxter, but with other models you only need to replace the sensors if the pads were let wear down enough to turn on the warning light.

 

[Guest]

There' s no such thing as a daft question, even from a girlie. Is the sensor embedded into the friction lining of the pad and as the pad wears, the sensor eventually touches the disc and completes an electrical circuit which causes the warning light to come on ? This was the system in use in the early 90' s on some types of car. Nic or JCB should be able to tell us for certain.

If you have a Boxster, why do you call yourself sporty911 ?????

 

[Guest]

hummm, my warning light hasn' t come on yet so I won' t buy new sensors .... unless anyone else can shed some more light on it.

Call myslef " sporty911" , because this is the alias I' ve used for years, on various message boards, from stock investments to errr cars!. I' ve only recently purchased a Boxster (as I can' t yet afford a 911, which I must admit, has always been my first love), and was too lazy to think of a new name when I signed up to the Boxster forums.

Cheers

 

[Guest]

The sensor actually appears to be a separate component. Check out http://www.bombaydigital.com/boxster/projects/brakes/change_pads
Being able to speak Americanese would be a help e.g. rotor=brake disc, colorized=shaded and vibration pad=shim

To be honest, I think you have struck gold with the Boxster. The 986 model and in particular the S gives you all of the 911 fun with none of the vices. No doubt there will now be an avalanche of hate mail from the 911 owners.

I' m looking forward to seeing the 997 model and may be tempted to go for a tin top next time just for the experience of owning one.

cheers

Brian

 

[Guest]

Brian

Yes, you are right, the sensor is a separate component. I' ve just bought front pads and sensor off ebay, and the sensors are errm separate. Just wasn' t sure if I needed to replace sensor as back pads and discs need replacing.

Having bought a Boxster I agree ITS FAB. ITS GREAT. I LOVE IT!!!!!!!!. The 911 was THE car to have when I was a wee girl (not that long ago I hasen to add [] ) and thats when I wanted one. I' ve just been infatuated with them ever since. Having driven the Boxster ........... I may just change my mind ...... however, may also go for a tin top next, as open top does no favours to my hey fever, sensitive skin, or paranoia about someone slashing the roof!

 

[Guest]

I' ve never heard of anyone having their roof slashed so I don' t think you have anything to worry about. I guess it depends where you live. Which part of the country are you in ?

 

[Guest]

I live in North Cheshire, on the outskirts of the car crime capital of Europe ... Manchester. A friend of mine had his hood slashed on his old Boxster (2001 2.7) ... lives in Altrincham, a rather well to do area in North Cheshire. Not stopped him from getting a new 3.2 S though!

Pip

 

[JCB..]

There is no need to replace the ' sensors' unless you are down to the rivets!

They are just a set of metal contacts that make a circuit when the pads wear sufficiently to allow them to touch the surface of the disc.

 

[Sean Dunne]

ORIGINAL: JCB..
They are just a set of metal contacts that make a circuit when the pads wear sufficiently to allow them to touch the surface of the disc.

At the risk of being pedantic, I thought the sensors worked the opposite way. When the pads wear sufficiently, a contact in the sensors is also worn through resulting on an open circuit that activates the warning light. This is why the sensors need to be replaced.

Also, some brake conversions that eliminate the sensors require the witing to be short circuited to turn off the warning light.

 

[JCB..]

Sean

I think you might be correct!

I' m trying to get a definitive answer which hasn' t been too easy so far.

I' ve had short circuit, open circuit and a combination of both so far!

HCB..

 

[Guest]

Well, just to add my twopenneth worth, the sensors on my 3.2 carrera are just a piece of insulated wire, U-shaped, inserted into each pad. When the pads wear down, the curved bit of the U has it' s insulation worn off by the disc, and the wire touches the disc - brake warning light comes on (and stays on). Luckily, they are dead cheap (by porker standards, anyway), being just a few pounds each.

 

[tim court]

Hmmm.... On my 996 the brake pad wear indicator came on during heavy braking, then went out as the pedal was released.

I checked the pads and they needed replacing. On inspection during pad replacement the wear indicators were worn away one side indicating contact with disc.

Put in new pads with old sensors and all is back to normal. This would indicate the disc, being earthed, closes the circuit.

I am sure it was the same with my previous (944S2), but could not be certain.

Perhaps Porsche have changed the operating philosophy???

 

[NicD]

This sounds right, the sensors sit in the pads (actually, the steel plate) at a predetermined distance from the discs. When the pads get too thin, the sensor wire touches the disk. light comes on.
So shouldnt matter if the insulation is wom away.

The hardest job I had when replacing mine a couple of months ago, was seperating the pad backing plate from the shim at the end of the piston. The heat had welded them together. Had to carefully lever them apart from the sides.

Now the new sintered pads do not judder on the track, so a result, though they do squeal a little sometimes, actually, now I think about this, it was only before the track day, rarely now.

 

[JCB..]

I have asked by buddy who runs a tyre shop or two to get us some info straight from the horses mouth.

I will post when I have a response.

JCB..