[fpena944]

Took a day off of work today and my dad and I just replaced all four corners of rotors and brakes on the CTT.

The wear indicators hadn't gone off yet but the fronts were pretty close to worn and I could feel a little bit of pulsating on the pedal telling me the rotors weren't in great shape either.

All went well and relatively easy but the parking brake is now complaining. My father has a Snap-On professional diagnostic machine from when he had his own shop. On there it has a procedure that backs out the parking brake so that you can replace the rear rotors. Doing so puts the brakes in what is referred to as service mode. So far so good, right?

Well when all is said and done, we put it back together hoping we can just re-calibrate the parking brake and be done with it. Nope, the car expects us to go through a procedure known as "grinding" where you're supposed to put the parking brake on and go up to 12 MPH for 100 feet then release the parking brake. It asks us to do this 8 times!!!

We didn't replace the parking brake shoes as they seemed fine. But if I go through this procedure I'm sure I'll destroy them. So does anyone know a way around this?

The brake still works and I drove the car home without issues but the "Parking Brake in Service Mode" message won't go away and won't reset itself unless we do this horrid procedure. Any alternatives?

[Scott at Team Harco]

What is meant by putting the parking brake 'on'? If it is just a simple mechanical application, maybe you can apply light load. I suspect it's probably electromechanical and thus there is no in between.

Sorry - not helpful. Maybe there are YT videos?

[fpena944]

What is meant by putting the parking brake 'on'? If it is just a simple mechanical application, maybe you can apply light load. I suspect it's probably electromechanical and thus there is no in between.

Sorry - not helpful. Maybe there are YT videos?

Basically the equivalent of a novice driver driving away with the parking brake still engaged!

Yes this is the procedure to re-calibrate the parking brake after you replace the rotor. Reminds me of why I keep my 996 as I can actually DIY that one without as much computer interference!

As for YouTube, I did check through it and yes this is what people discuss doing. But I need to dig deeper and see if there are any alternatives.

[N_Jay]

there it has a procedure that backs out the

Don't worry about ruining the barking brake shoes.

Just do what it wants.

[fpena944]

there it has a procedure that backs out the

Don't worry about ruining the barking brake shoes.

Just do what it wants.

If I can't figure out a way around it, then that's just what we'll have to do. I probably won't be left with any parking brakes afterwards though.

[N_Jay]

100 feet is not going to destroy your parking barkes

[fpena944]

100 feet is not going to destroy your parking barkes

If it were once I would agree with you. But it asks us to do this process eight times.

[N_Jay]

Still would not worry

[fpena944]

Still would not worry

I'll let you all know how it goes. It'll be one of those "hold me beer!" moments.

[tooloud10]

Seems odd, I guess I may have misunderstood the point of electric parking brakes--I was always under the impression that they were cheaper/simpler to include on new cars because they didn't require additional hardware and could just activate the regular rear brakes 'at will' in order to hold the car.

Am I totally wrong there or is there a reason that Porsche still uses separate parking brake calipers even though it's electrically actuated?

[SeanR]

This is why when I do rear brakes on a modern car with the electrical brake activation, I open the door, turn on the key, release the parking brake. Then install new pads/rotors and when done I turn off the key. Don't have to screw with any computers or calibrations.

[fpena944]

Seems odd, I guess I may have misunderstood the point of electric parking brakes--I was always under the impression that they were cheaper/simpler to include on new cars because they didn't require additional hardware and could just activate the regular rear brakes 'at will' in order to hold the car.

Am I totally wrong there or is there a reason that Porsche still uses separate parking brake calipers even though it's electrically actuated?

On cars like the BMW it is what you just described. But on the Cayenne you still have the traditional drum brake in the back but it's just electronically actuated. I think on the 1st gen Cayenne's there is a manual adjustment because I saw someone on YouTube referring to it but not on the 958.

Nonetheless what should have been simpler instead is more complex and impossible to do unless you have the right computer to hook up to.

This is why when I do rear brakes on a modern car with the electrical brake activation, I open the door, turn on the key, release the parking brake. Then install new pads/rotors and when done I turn off the key. Don't have to screw with any computers or calibrations.

In hindsight that seems like a wonderful idea. Not sure it would have worked though because we needed to tell the computer to back the shoes off the drum or we wouldn't have been able to remove it. Once that is done then it automatically goes into service mode and you're stuck having to re-calibrate before going back to normal.

[fpena944]

We did it!

Ok I stand corrected that you cannot make adjustments manually. We took the calipers and rotors back off and found an adjustment screw. Tapped it with a flathead screwdriver a few times and let the computer take measurements again. This time it said that we were within range so all good, right?

Not at all...Instead we then got stuck again on the "grinding part" but this time it told us if we had already ground the brakes we could just proceed. Now we tested the parking brake and it was grabbing great (even on an inclined driveway) so we told the Cayenne a white lie by answering that we have NOT changed the rotors and were re-using old parts.

Once we did that then everything went through without incident and the error message is gone!

Can't believe that now to finish what used to be a simple job you now have to lie to your vehicle. Progress, right?

[i am not a traitor]

We did it!

Ok I stand corrected that you cannot make adjustments manually. We took the calipers and rotors back off and found an adjustment screw. Tapped it with a flathead screwdriver a few times and let the computer take measurements again. This time it said that we were within range so all good, right?

Not at all...Instead we then got stuck again on the "grinding part" but this time it told us if we had already ground the brakes we could just proceed. Now we tested the parking brake and it was grabbing great (even on an inclined driveway) so we told the Cayenne a white lie by answering that we have NOT changed the rotors and were re-using old parts.

Once we did that then everything went through without incident and the error message is gone!

Can't believe that now to finish what used to be a simple job you now have to lie to your vehicle. Progress, right?

I'll be replacing the rear pads/rotors on the Pilot tomorrow. Sooo glad that I won't have to deal with that nonsense!

[fpena944]

We did it!

Ok I stand corrected that you cannot make adjustments manually. We took the calipers and rotors back off and found an adjustment screw. Tapped it with a flathead screwdriver a few times and let the computer take measurements again. This time it said that we were within range so all good, right?

Not at all...Instead we then got stuck again on the "grinding part" but this time it told us if we had already ground the brakes we could just proceed. Now we tested the parking brake and it was grabbing great (even on an inclined driveway) so we told the Cayenne a white lie by answering that we have NOT changed the rotors and were re-using old parts.

Once we did that then everything went through without incident and the error message is gone!

Can't believe that now to finish what used to be a simple job you now have to lie to your vehicle. Progress, right?

I'll be replacing the rear pads/rotors on the Pilot tomorrow. Sooo glad that I won't have to deal with that nonsense!

This is why I'm keeping my 2002 911. There will come a time when we won't be allowed to touch our own vehicles anymore so it'll be nice to have something to play with when that day arrives.

Good luck on that job!

[N_Jay]

We did it!

Ok I stand corrected that you cannot make adjustments manually. We took the calipers and rotors back off and found an adjustment screw. Tapped it with a flathead screwdriver a few times and let the computer take measurements again. This time it said that we were within range so all good, right?

Not at all...Instead we then got stuck again on the "grinding part" but this time it told us if we had already ground the brakes we could just proceed. Now we tested the parking brake and it was grabbing great (even on an inclined driveway) so we told the Cayenne a white lie by answering that we have NOT changed the rotors and were re-using old parts.

Once we did that then everything went through without incident and the error message is gone!

Can't believe that now to finish what used to be a simple job you now have to lie to your vehicle. Progress, right?

I'll be replacing the rear pads/rotors on the Pilot tomorrow. Sooo glad that I won't have to deal with that nonsense!

Instead you will remove a small rubber plug. That will hide among the last 10mm sockets.
Turn the hub to mysterious position 67, and insert a screwdriver into the hole in search of the elusive adjuster.