Lexmark C750 Service Manual - Page 80

5060-00x 122 Error code The printer has detected a problem in the fuser hot roll lamp circuitry, backup roll fuser circuitry, fuser hot roll thermistor, backup roll thermistor, engine board, or LVPS fuser control circuits. Replace the FRUs in the order shown: 1. Fuser assembly. See "Fuser assembly removal" on page 4-31. 2. LVPS assembly. See "Low voltage power supply (LVPS) removal" on page 4-38. 3. Engine board. See "Engine board removal" on page 4-29. 123 Error code Cold fuser The printer has detected a problem in the fuser hot roll lamp circuits, backup roll fuser lamp circuits, fuser hot roll thermistor, backup roll thermistor, engine board, or LVPS fuser control circuits. Replace the FRUs in the order shown: 1. Fuser assembly. See "Fuser assembly removal" on page 4-31. 2. LVPS assembly. See "Low voltage power supply (LVPS) removal" on page 4-38. 3. Engine board. See "Engine board removal" on page 4-29. 124 Error code Hot fuser The printer detects a problem with the fuser running over temperature or the hot roll fuser lamp has been on too long. A problem may exist in the fuser assembly with the hot roll bearings, the hot roll thermistor, or other hot roll parts. The LVPS or engine board assembly can also be failing. Step 1 Action and questions Open the right fuser access door. Observe the fuser and see if the hot roll lamp turns on and off. You may have to observe the fuser for a few minutes. Does the hot roll lamp turn off and on? Yes Go to step 2 No Replace the LVPS assembly. See "Low voltage power supply (LVPS) removal" on page 4-38. Replace the engine board assembly. See "Engine board removal" on page 4-29. 2 Turn the printer on and measure the voltage on connector J10-11 on the engine board. The voltage should measure approximately +0.13 V dc to +0.64 V dc as the hot roll lamp turns on and off. Is the voltage correct? Replace the fuser assembly. See "Fuser assembly removal" on page 4-31. 2-46 Service Manual