Tach warning lights

On my 2004 C2, 6 speed stick, every time I use the car (101k miles), on the dashboard, the bottom third of the tach lights up with red warning letters "BREAK WEAR Service wear on brake pads". When I push the stick on the left of the column, it goes out. However, a red circular "idiot light" light below the tach displaying "Service" stays on. I freaked when it first did it, and took the car to my local service guy 9elf in Santa Rosa. He checked the brakes out & said everything was ok. It is a nuisance however, as the warning letters come on anywhere from 50' to 250', and the idiot light stays on forever. Does anyone know of a solution for this annoyance? Thank you, Tomas in Sebastopol

Are your brake pad sensors good. Sent from my iPhone using Rennlist

Rotors and pad thickness might be okay, but everything is not okay if your wear indicator is on. There is a brake wear indicator (simple switch) at each wheel inserted at a brake pad. A wire might have been nicked creating a bare wire or a wire could be pinched. Really a pretty simple fix to have it replaced, it only takes one indicator to fail to trip the fault reading. In the scheme of Porsche repair costs this one is on the low side. If you are mechanically inclined you can DIY. There is also a way to disable the wear indicators but someone else will need to chime in on that method.

The brake pads can be a bit of work to really check. The car has to be lifted up and each pad checked for thickness. The pads can wear unevenly from front to back of the pad and top to bottom. Thus a perfectly thick enough pad when viewed from one end or above can look just fine while the pad is worn enough the wear sensor is making contact with the rotor. Assuming the brake pads are all ok, you still got half a job as the tech then should have looked at the sensors. This can be a bit more work as the sensor may be bad where it is routed through the clip that holds the pads from moving about and being bad is hard to spot. Almost certainly the wheel would have to be removed and each sensor and its wiring checked. You might try this: Wash the brakes. I do this at a DIY car wash. I set the wash wand control to soap then give each wheel brake a good spraying. Then I select rinse and rinse each one. Last I finish with the no spot rinse. This setting the nozzle pressure is reduced so I can the wand tip closer -- but not too close -- the calipers/pads to rinse away the brake dust that collects on the pads but on the caliper piston dust boots as well. After you do this be sure you drive the car and use the brakes hard enough and often enough to get them hot enough to dry all the water. Put the car away with wet brake hardware and the brakes can give you more trouble. I usually recommend the above washing for brakes that are lightly squealing. In your car's case I'm thinking enough dust has collected that the dust is shorting the wear sensor. The real problem is the sensor probably needs to be replaced but you don't know which sensor so you could have to replace all 4. Or replace one at a time until you hit the bad one.

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Track guys just disconnect and zip tie out of the way. Sent from my iPhone using Rennlist

Macster, I normally agree with your diagnoses, but my understanding of the wear sensors on this platform is a single continuous closed circuit, with any corner wearing through resulting in a broken loop. How does moisture affect this system?

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This is true...mine are zip tied to the brake lines. If your sensors are intact, extract the plug from each pad with needle-nose pliers and zip 'em up out of the way...

If you are a DIY man, change the brakes pads and wear sensors. You can't be arsing about with brakes. It's easier to go that route than mess about. Be careful with the new sensors as they are delicate. Bleed the brake system when you are in there.

i guess wear sensors are good,if you never check your pads,and or keep records of when you replaced the pads last,otherwise you dont need them.

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Here's a question... Why didn't your service guy check and/or replace the brake wear sensors? (or do a more thorough inspection of the brake pads?) If the dashboard indicator is illuminating, he should have figured out this simple check.

Last time I replaced the brake pads I replaced the sensor cables as well. It's a damn simple job, plug and play. Got Bosch sensor cables from Discount Auto parts for something like $13/per axle. Got to agree, your service guy is an idiot. If you can't DIY, find a new service guy asap. Every car made in the past ten years (maybe more) has the same system, so this is not some special Porsche mystery.

I've reused brake sensors in the past I admit. I've also noticed due to extreme heat of the brake components that the plastic around the sensor can have a good chance of becoming brittle and break apart. When this happens you have a good chance of getting a false error. As some others, I usually just zip tie mine out of the way now as I'm one of the "few" that actually check my tire pressures, oil, brake pads, coolant amongst others manually.

How is your brake fluid level?

re: the brake warning light. Thanks for your responses. The mechanic is not an idiot, it's Michael at 9Elf, in Santa Rosa. He used to work at Sonnen Porsche in San Rafael. He does service at about half the price of the dealer, & has fixed things for free, like headlamp bulbs. I'm not a DIY on this car. I used to on my old '63 VW, but I'm not dumb enough to try to fix something on this car. I will take all the replies to 9Elf & ask him to investigate.

If youre not going to DIY and you believe and trust your indy then why bother asking questions here. Not trying to be an ******* but it just seems like youre advertising your shop.

Hate those freakin' sensors... Also in the cut/twist/epoxy-shrink-wrap/zip-tie-out-of-the-way camp. That said, if your not the kind of person that actually looks at their brake pads to check for wear, better to replace them if needed and leave them in place.