Kyocera KM-2020

2C9-2
1-5-19
Code Contents
Remarks
Causes Check procedures/corrective measures
C6400
C7800
C7810
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
Broken external temperature ther-
mistor
• The input voltage is 0.5 V or less.
Short-circuited external temperature
thermistor
• The input voltage is 4.5 V or more.
Poor contact in
the connector ter-
minals.
Defective power
supply PCB.
Defective engine
PCB.
Poor contact in
the humidity sen-
sor connector ter-
minals.
Defective humidity
sensor.
Poor contact in
the humidity sen-
sor connector ter-
minals.
Defective humidity
sensor.
Reinsert the connector. Also check for con-
tinuity within the connector cable. If none,
remedy or replace the cable.
Check if the zero-crossing signal is output
from CN2-5 on the power supply PCB. If
not, replace the power supply PCB.
Replace the engine PCB if C640 is de-
tected while CN2-5 on the power supply
PCB outputs the zero-crossing signal.
Reinsert the connector. Also check for con-
tinuity within the connector cable. If none,
remedy or replace the cable.
Replace the drawer PCB and check for
correct operation.
Reinsert the connector. Also check for con-
tinuity within the connector cable. If none,
remedy or replace the cable.
Replace the drawer PCB and check for
correct operation.