Nates

So my 2013 c250 has the ABS light and engine light on, it’s reading c0031, I just changed the front left speed censor and erased the engine code, i tired but couldn’t erase the ABS code. The engine light came back and the ABS light is still there. Also sometimes the ABS light will go off and the coffee cup with come on to replace it, and the ABS light will come back and the attention assist is go away, what’s going on here?

Odd Piggy

Either the new sensor is faulty, the wiring harness is broken, or the harness is shorted. Can your scanner read real time data from the ABS circuit? That may help define the problem.

Nates

unfortunately I have a cheap obd but when you say harness do you mean the wires that are attached to the sensor or another part? I was thinking about changing the left and right sensors and seeing if the code jumps

Odd Piggy

When I said harness, I was referring to the sensor wiring anywhere. When it breaks, causing an open circuit, it is usually near the wheel.
Your idea about swapping left and right sensors is a good one. If the problem moves, then it is definitely the sensor. If it does not, then the problem is somewhere on the left side.