Showing fault C0288... Brake pad wear signal circuit. The pads appear to be new. possible causes faulty master cylinder pressure sensor or faulty yaw rate sensor/lateral accelerometer .. anyone have this in the past what is the fix. thanks..

 

Pure BS! One or more of the brake pad wear sensors or the associated wiring is damaged. You can replace the sensor or just splice the wires together at the sensor.

 

The only thing in your list that C0288 involves is the EBCM. Wherever you got that list of potential trouble items from it is wrong.

Here is the diagnostic and the related schematic:



As you can see the brake wear sensor for the J57 Ceramic Brake Rotor cars is part of a serial circuit. The sensor is a pill with a wire running through it that wears down when it starts hitting the rotor. When the brake rotor breaks the wire inside the sensor that breaks the circuit and lights the brake worn message along with setting the code. With new or non-worn pads what typically happens is the sensor on one of the inside brake pads is placed incorrectly on the pad and it prematurely wears through breaking the circuit shown in the schematic.

The first thing you need to do is pull the wheels and inspect each of the 4 inside brake pads to determine if one or more sensors are worn through. If you find a sensor with a broken wire (usually visible when looking at the sensor after the pad is removed from the caliper) you either need to replace a worn brake pad or a worn sensor. GM used to only provide the sensors with the pads but since they have had a lot of brakes worn messages when the brakes weren't actually worn they have started selling the sensors separately. Replacing the sensor is easy in concept but the connector where it fastens to one of the chassis harnesses is tightly wound in tape and mounted to the cradle near the suspension level sensor at each wheel location. It can take some effort to free the connector sufficiently and be able to disconnect it. I found this out when replacing worn brake pads at the track with the car on jack stands while sitting/laying on hot asphalt trying to get 4 connectors disconnected, The time taken may have seemed longer than it was with sweat pouring into my eyes and the heat from the asphalt burning my butt and legs.

If you don't find a worn brake sensor pill you could have a broken wire in one of the sensor harnesses. That means removing the sensors and checking each one of them with a continuity tester to make sure they don't have broken wire. This can be a PIA since the circuit is a serial circuit and is like a string of cheap Christmas tree lights where if one bulb burns out you need to keep changing bulbs until you find the one that is burned out.

If you don't find any of these issues then you will need to follow the other parts of the diagnostic to find the fault. It is rare that an EBCM needs to be replaced.

Bill

 

This is the brake pad sensor, you need to check the brake pads out and replace the offending sensor or jumper it as suggested.

 

After doing a Google search for C0288 I came upon the following website that has the erroneous information about C0288: www.engine-codes.com

The site may have innocently printed incorrect information or is poorly edited. At best we know it has obvious errors.

I would suggest not using that site for any diagnostic information.

Bill

 

Thank you everyone I will pull the wheels off tomorrow and see if I can see the pad sensor. The pads appear to be fairly new.

 

You probably don't have the foam protectors for the rotors, so come up with some measures to ensure that the wheel does not chip the rotor when you remove it or you will have a much more expensive problem.

 

If you don't have the rotor protectors go to Home Depot or Lowes and purchase foam pipe insulation. Just make sure it is a large enough diameter to fit over the rotor which is 33/34 mm (~1 5/16) thick.

Bill

 

I took off all four tires today inspected all the brakes they look brand new. I suspect the brake pads were changed and the sensors were not the sensors are about 43.00 a piece. I moved around all the wires inspected them they all appeared to be good. Put all 4 wheels back on the car which is a pain in the *** went for a ride and the warning on the instrument cluster went away. I have not checked it again on the Autel because I don't want to jinx myself..lol Lets see how long this lasts.. Thanks again for all the replies.

 

I will do this I remember my 16 came with those white inserts.

 

If they installed new GM pads the pads come with new sensors already installed on the pads. If they installed non-GM pads then the sensors may have been reused and may be causing a problem. The fault occurs because there is a break in the wiring, either in the sensor itself or in the harness. I don't see a worn-through sensor healing itself by moving it around. However, a broken wire surrounded by insulation might do that for a short time. If the fault comes back it will be time to check the wiring using a continuity checker.

Bill

 

Bill I agree if a wire is broke or the sensor was eaten threw I don't see how it can work but here we are I must have moved something somewhere that made a connection. The sensor wires looked new and clean. I drove the car today and so far no error messages. Time will tell.

 

Check the connectors where the sensor harnesses plug into the car harness on the cradles. Maybe one of them isn't seated correctly.

Bill