To examine other circuit whether there is fault, try to make a box to remove anti wipe programs with pushed into the cabin, reproduction, just can't function operation, accordingly can judge the machine is only damage IC7501 M37422V4AF. Because of the temporary purchase less than the prototype integrated block, the author through to find relevant information found its available JPC2003BV4AF type integrated block to direct substitution. The resistance between the foot and the 32 foot of the JPC2003BV4AF type integrated block is shown in the schedule. After replacing the IC7501 with the JPC2003BV4AF type block, the test machine is restored to normal.

Summary: due to damage to the foot IC750117 internal circuit, is that the receiving the serial clock signal sent to the foot of the IC200144, resulting in serial data transmission and IC2001 cannot, caused by the artificial operation instruction is transmitted to the IC2001, which leads to the occurrence of the fault in this case.