KM-1650

[bviles20]

I have one KM-1650 in the field. It belong to a friend of mine so I told hime I would try to service it. When you turn the machine on it pops a c6400 code. It says its a zero crossing signal problem. Does anyone know what I can check before I start replacing PCB's. Any help is appreciated.

[10871087]

I have one KM-1650 in the field. It belong to a friend of mine so I told hime I would try to service it. When you turn the machine on it pops a c6400 code. It says its a zero crossing signal problem. Does anyone know what I can check before I start replacing PCB's. Any help is appreciated.


I havn't run into that one before, hopefully you can reseat some connectors and bring it back to life without having to buy some pretty spendy parts. Here is what the book says:



C6400 - Zero-crossing signal problem
The engine PCB does not detect the zero-crossing signal for the time specified below. At power-on: 3 s Others: 5 s

Possible Causes:


Poor contact in the connector terminals.
Reinsert the connector. Also check for continuity within the connector cable. If none, remedy or replace the cable.


Defective power supply PCB.
Check if the zero-crossing signal is output from YC2-5 on the power supply PCB. If not, replace the power supply PCB.


Defective engine PCB.
Replace the engine PCB if C6400 is detected while YC2-5 on the power supply PCB outputs the zero-crossing signal.

[bviles20]

Thanks for the help for future reference I just ran sim 163 and it cleared up. The customer had a power outage due to a thunderstorm I think that is the root of the problem.

[10871087]

Thanks for the follow-up! I will store that away in the area of my brain that has not rotted away yet.:)

[KJ1110]

Check the stability of their power outlet; I've found bad power to be the cause of a LOT of "False Codes" with Digital machines, usually they seem to present as fuser problems!

[higherlevel]

I do not have the Service manual in front of me, but zero crossing has to do with power stabilization of the Fuser unit....