Lexmark C750 Service Manual - Page 85

5060-00x 131 Error code The fuser backup roll does not reach the correct standby temperature. Step 1 Action and questions Measure the voltage on connector J10-12 on the engine board. See "Engine board" on page 5-7 for the location of the connector. The voltage should measure approximately +0.13 V dc to 0.64 V dc as the backup roll lamp turns on and off. Is the voltage correct? 2 Remove the fuser from the printer. Check the continuity of the backup roll lamp by measuring between pins 2 and 5 on the AC fuser connector on the fuser assembly. Go to step 5 Go to step 3 Yes Replace the fuser assembly. See "Fuser assembly removal" on page 4-31. No Go to step 2 Is there continuity? 3 Check to make sure the backup roll lamp is installed correctly. Is the lamp installed correctly? 4 Carefully remove the lamp from the fuser assembly, being careful to only handle the lamp by the ceramic end pieces and not by the glass envelope. Warning: Use caution when handling the lamp as it is easily broken. Check the continuity of the backup roll lamp. Is there continuity? 5 Reinstall the fuser assembly. Watch to see if the lamps turn on and off as the lamps heat up. Do the lamps turn on and off? Go to step 6 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. Replace the fuser assembly. See "Fuser assembly removal" on page 4-31. Replace the backup roll lamp. Go to step 4 Install the lamp correctly. 6 Turn the printer on and allow it to reach Ready. Note: The printer may not complete POR and continues to display a 131 error. Remove the fuser assembly from the printer and measure the voltage on connector J10-7 on the engine board. The voltage should measure approximately +3.3 V dc. Is the voltage correct? Go to step 7 Diagnostic information 2-51