Error Messages and Codes 3-27
Fuser STS (Front) Warm Time Failure, Code 42
Main heater warm-up error. The temperature did not reach the “Ready” temperature 
within the specified time.
Fuser SSR1 On Time Failure, Code 43
The main heater remained ON for more than the specified time.
Troubleshooting References 
Applicable Parts Wiring and Plug/Jack Map References
■ Fuser
■ Engine Control Board
Troubleshooting Procedure 
Step Actions and Questions Yes No
1
1. Turn OFF power, remove the Fuser 
Assembly and allow it to cool down.
2. Measure the resistance between the 
Fuser connector P600-4 and P600-6.
3. Does the resistance measure between 
30 K and 190 K Ohms?
Go to step 2. Replace the fuser 
assembly.
2
1. Measure the resistance between fuser 
connector P600-1 and P600-12.
2. Does the resistance measure 20 Ohms 
or less?
Go to step 3. Replace the fuser 
assembly.
3
1. Reinstall the fuser assembly.
2. Enter service diagnostics.
3. From the Sensor Tests run the Fuser 
Temperature test.
4. Is the temperature indicated 
approximately 165
o 
C?
Go to step 5. Go to step 4.
4
1. Turn OFF the printer power.
2. Check for an open circuit or poor 
connection between J641-2 and 
J404A-2.
3. Is the wiring OK?
Replace the 
engine control 
board.
Repair or replace 
the wiring 
harness.