My Kyocera KM 1635 / 2035 displays error message: error call 600

SOURCE: error code C-6 for kyocera km 1500

Fuser error,
may have either a blown lamp, blown thermo fuse or faulty thermistors, but more then likely a combination of at least two.

SOURCE: km-1510 .. AP error code

Did lamp under platen lit ? If not,probably you need to replace or vacuum waste toner reservoir and transport of toner from toner bottle in developer unit.

SOURCE: Kyocera Mita 1500 Error code 6000

This C6000 error code is triggered by a few things all having to do with the fixing heater wire. Ask your technician to check the thermistor, the thermal cutout and the connection between the thermistor and the power supply board. My guess would be that the power surge overloaded the power supply board. This is not something that can be reset and may require new parts.
The manuals that describe the error codes are only available to Kyocera technicians, sorry.
Henry

SOURCE: MY COPIER (KYOCERA 1635) DISPLAS ERROR C6050. HOW

C6050 Abnormally low fuser unit thermistor temperature The fuser temperature remains below 90°C/194°F for 1 s. Poor contact in the thermistor connector terminals. Reinsert the connector. Also check for continuity within the connector cable. If none, remedy or replace the cable. Broken fuser thermistor wire. Measure the resistance. If it is ∞ ω, replace the fuser thermistor. Fuser thermistor installed incorrectly. Check and reinstall if necessary. Fuser thermostat triggered. Check for continuity. If none, replace the fuser thermostat. Fuser heater M or S installed incorrectly. Check and reinstall if necessary. Broken fuser heater M or S wire. Check for continuity. If none, replace the fuser heater M or S. Code Contents Remarks Causes Check procedures/corrective measures

SOURCE: How to solve error c6020 for Kyocera KM-2035

The C6020 is a fuser error code and should be checked out by a Kyocera tech.