Chevy Cust Svc

pinoyZR1,
I agree with the others. I'd definitely go to your dealership and insist they check all of the sensors. It's always better to be safe than sorry. If you need help setting up an appointment let me know and I'll be happy to help you.

Chevrolet Customer Service,
Justin

pinoyZR1

Thanks Justin. Just got the car back, sensors ok, pads great, passed all electrical tolerances........ plan now to change module. But, on back order. Apparently, there are no dealerships in the US with the brake module in stock. Warning light still on! I guess I'll just have to wait for delphi to make the module. Module is apparently different from Z06.

Fast & Lazy

JVP is absolutely correct. I have just replaced my pads and learned quite a bit.

The 4 sensors complete a simple circuit. When the circuit is broken the "brake pad" indicator will light up on the DIC. I have looked at the circuit and it appears that the sensors MUST be plugged into the circuit but it doesn't matter if they are actually inserted into the slot in the brake pad (not that you would EVER want them just dangling but just from and electrical point of view).

When the pad wears down enough for the rotor to rub the sensor it will very quickly destroy enough of the metal inside the sensor to open the circuit causing the indicator to light up.

Any of the 4 sensors will do the same thing as they are all in a series connection and any of them can break the circuit. You never know which one is the culprit until you check the sensors/pads.

((BTW, when you buy a new set of pads you will get new sensors as well. Be aware that there are two different lengths of the sensors. The longer ones go to the FR and LR wheels as they are inserted at the bottom of the inner pad and the FL and RR are inserted at the top of the inner pad.....thus the need for longer wires for the FR & LR.....I mention this as there is no indication of this in the Pad/Sensor replacement procedure that is to be used by the GM techs and it bit me but I figured it out.))

I haven't check this but from the circuit diagram it appears that if the sensor wire (the actual wire) comes loose or is disconnected, it would look the same to the brake module as an open circuit and the indicator would light up. I believe that the open circuit or a short to ground each generate a DTC code:

DTC C0288 00: Brake Pad Wear Signal Circuit
DTC C0288 02: Brake Pad Wear Signal Circuit Short to Ground

This all comes from Document ID:2370420

I highly recommend that you check with your service tech that tested your brake pads, sensors, electrical tolerances, etc... to make sure that he followed the procedure in this document in section "Circuit/System Testing" as it is very specific on how to check the ECBM (electronic brake control module) and the sensor circuit. It actually indicates that the sensor circuit connector to the ECBM should be disconnected before testing the circuit.

If he didn't follow this procedure you might be barking up the wrong tree. It is possible that you just have a faulty sensor or the wire pulled loose somehow.....and waiting for a new ECBM might not only be a long wait but not necessary. The sensors are cheap and easy to check.

In fact, you wouldn't even have to remove the pads to check this. You can just test each wheel by disconnecting the sensor from the plug at the inside of the caliper (you can just leave the wear part of the sensor inserted in the pad) and plugging in a new sensor to see if that corrects the problem (ie., completes the circuit). If not, plug the original back in and try the next wheel.

Hope this helps.

Fast & Lazy

Chevy Cust Svc

pinoyZR1,
You're more than welcome. I'm sorry to hear that they don't have your part anywhere. However, at least they didn't discover a more serious issue. Let me know if there's anything I can do to help.

Chevrolet Customer Service,
Justin

Trapper Sean

That's great info. Should probably be a sticky or otherwise archived for future use.

pinoyZR1

Thanks for the info. The tech mentioned that tolerances were OK but is there a way to check the connections yourself? Does the wheels need to come off?

Fast & Lazy

First, how did he determine that the tolerances were OK? If he followed the procedure in the doc I mentioned, then he probably gave you good info. If not....then you have unreliable info.

Next, you can check each sensor with a meter to see if it is broken. You will have to remove the wheels. Behind each caliper the sensor "plug" is attached to a bracket which is held in place by the upper caliper bolt. This is where the "system" connector plugs in to connect to the sensor. You can disconnect the system plug end from the sensor and then measure the resistance between the two wires in the plug end of the sensor (the plug that is still attached to the bracket). You can leave the "wear" part of the sensor in the brake pad.

The two wires should be "shorted" together as they are really just one wire looped through the wear part of the sensor that is attached to the pad. If the wires in the plug are NOT shorted together then the sensor is broken and that would be a source for the pad replacement indicator.

This is really pretty easy once you remove the wheels. If you have any questions please send me an email (I don't see private messages very quickly). It is not difficult to remove the sensor completely from the bracket and the pad if you need to do so. Just be mindful of how the sensor is inserted into the pad so it is done correctly.

If it is too hard to get the meter probes into the plug, you could easily remove the plug from the bracket and then there is lots of slack. You will see what I mean when you look behind the caliper. I don't have any photos for your as my wheels are on the car and will not be taking them off again until tomorrow at which time I could take some photos.

Good Luck,

Fast & Lazy

pinoyZR1

I've got a lift. Would I be able to avoid taking the wheels off and check the sensors from underneath the car? Another question will be.. what is the chance that the tech did it right? I mean, some people might find it offensive if I ask them repeatedly if they did the checks right. I guess I could go to another dealership but then again, there are no local dealerships that have zr1 sales. Most if not all zr1s in town were specially ordered.

Fast & Lazy

First, I don't know about getting to the sensor connector without taking the wheels off. You could try. I know for sure it would be easier without the wheels on. I don't have a lift at home and I do as little as possible from under the car as it is cramped for space and I am no spring chicken.

As far as the tech at the dealer goes, if you are concerned about approaching him with "interrogating" questions (I would have no problem with that but.....that's me), then I would suggest that you manually check each sensor yourself. ((You can always ask him if he can show you the documentation for the procedure he followed....so you can understand what's going on.....))

If you are going to check the sensors I would make sure and check all 4 brake pad sensors as if one is bad there might be more than one bad for the same reason....whatever that may be.

If you find one or more bad sensors, then you know for sure that the tech did NOT check your system properly. If all sensors are good and you still have the indicator light on, then it sure seems like the problem could be with the EBCM.

I hope this helps.....if you would like to speak on the phone, email to me (don't PM as I don't see private messages very quickly) with your phone number and I will be glad to give you a call.

Good luck,

Fast & Lazy

pinoyZR1

Alarm is off again this afternoon. Looks to me like there's a wire loose or hopefully just a connection.

Fast & Lazy

I would make no assumptions.....especially when it comes to the brake system. There is so much electronics in this car that "jumping to conclusions" is not a very good exercise.

Please check it out and be sure.

F & L

BEZ06

If you can get under the car, or put it on your lift, I think you should be able to access the pad sensor connectors through he backside of the wheels without removing them.

Below are some graphics out of the 2010 Service Manual.

Bob


Below are two pics of the front:








Below are pics of the rear:

pinoyZR1

Bob that is great! Exactly what I was looking for. Thank you. Will put her up on the lift and check all 4 connectio. We'll see if it males the alarm go away.

range96

This would indicate that the left and right side pads are interchangable. It also means that on the Left side (front and back) the sensors are on the trailing side of the pads and on the Right side (front and back) the sensors are on the leading side of the pads.

I'm curious as to why this configuration was chosen.

Fast & Lazy

The front pads are all the same and the rears are all the same (ie., interchangeable). Thus, the location of the "notch" where the sensor is inserted into the inner pad is going to be on the top on two of the wheels and the bottom on two of the wheels as it is always connected to the inner pad.

I would assume it was more cost effective to make the pads all the same (many more of them are manufactured) and individualize the rotors as the sensor wire restraining "notch" is on the top on one front and rear and the bottom on the other.

It's not easy to second guess Brembo......

Fast & Lazy