Boot protection, the power indicator light flash 8 times, according to the flicker frequency, bad for SS plate, protection, measuring the positive have a high level of the SS board D6255, shows that action of SS plate protection circuit, observe the leds D6253 shine in front of the protection by detecting voltage is not lost. Disconnect D6255 protection circuit, boot image (no obvious exception). Sx5service manual download site
Measuring IC6251 (2 feet 5 v, 5 feet 10 v, 13 v 6 feet (normal machine for around 7 v), end feet 15 v, that is 6 feet to detect voltage caused by abnormal protection. Sx5service manual download site
 Sx5service manual download site
 Sx5service manual download site
According to customer reflect, the machines use 3 hours after bad, have some parts hard bad, key measurements for short circuit, resistance significantly larger or open circuit. Sx5service manual download site
R6252, R6253, 6254 normal, measurement Q6051 has short circuit, after the change is normal.Sx5service manual download site