Hi there,
I am looking into buying a 8340A with known problem — Fault light on, fault code ADC. From the service manual, it says ADC fault indicates CPU detected ADC circuit problem on A27 level control assembly. When ADC is faulting, SYTM won’t track and won’t peak.
However, the manual has very little information on A27 troubleshooting. What would have caused the ADC fault? How does the power-on-self-test determine the ADC circuit is bad? Could it be as simple as bad reference voltage on the ADC or something very involved?
Thank you!
Calvin
