The invention discloses a CABC module repairing system and method. The system comprises a CABC module, a first register and a second register and further comprises an initial value register, a first logic circuit, a second logic circuit, a third logic circuit and a fourth logic circuit, wherein the first logic circuit conducts logical operation on the proof test value of the first register to obtain an intermediate value which corresponds to an abnormal bit in the first register and is different from a normal bit, the second logic circuit conducts logic operation on intermediate values and initial values to obtain a first correction value which corresponds to the abnormal bit and is equal to the value, corresponding to the abnormal bit, in the initial values, the third logic circuit conducts logic operation on intermediate values and initial values subjected to non-logic operation to obtain a second correction value which corresponds to the normal bit and is equal to the value, corresponding to the normal bit, in the initial values, the fourth logic circuit conducts logic operation on the first correction value and the second correction value to obtain a result after the initial values are input into the first register which is not broken, and the result serves as the input value of the second register to control the duty ratio of CABC output PWM waveforms.