Oki ES3640MFP Service & Troubleshooting Manual page 99

Environmental Sensor Failure
The Environmental Sensor has failed.
Error Codes that Apply
123 and 124
Initial Troubleshooting Actions to Take
1. Cycle the printer's power.
2. If the problem persists follow the procedure below.
Parts of the Printer that Apply
1. Environmental Sensor
2. Environmental Sensor Wiring
3. Engine Control Board
Troubleshooting Procedure
Steps
Test the Temp/Humidity Sensor.
1. Run the Scan Switch Test
1
2. Verify proper operation by blowing
on the sensor. Is the sensor operating
Replace the Temp/Humidity Sensor.
2
Check the Environmental Sensor
3
Wiring. Is it properly connected and
Action Taken
HUM_TEMP_OHP
correctly?
Does the error persist?
undamaged?
Yes
Replace the Engine
Control Board
Go to Step 3.
Reconnect/Repair
Wiring Harness
No
Go to Step 2.
Complete
Replace the Front
Sensor Board / Motor
Driver Board / Engine
Board in order.