Lexmark 4227 Service Manual - Page 40
Intermittent problem service check, FRU/Symptom, Action
UPC - 734646117104
View all Lexmark 4227 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 40 highlights
4227-300 Intermittent problem service check FRU/Symptom 1 The machine sometimes fails before POST is complete. Action Check for the following: 1. Loose connectors. Reconnect all connectors to the main and sub logic boards. 2. Electrical noise or static discharge. Check the following items: • Power supply ground • Machine frame ground • Printer interface cable is grounded and shielded. 3. Intermittently low voltages. Check for ac and all dc voltages and short-circuits on the main and sub logic boards. a. Check the electrical voltage and ensure that it is within tolerance. b. Check the continuity of the power cord. c. Disconnect the power supply cable from the connectors CN11 on the main logic board and CN1 on the sub logic board. Turn the printer power on and check all dc output voltages at CN11 and CN1. Ensure the output voltages are: CN11-1 (+40 ±4 V dc) & CN11-3 (GND) CN11-2 (+40 ±4 V dc) & CN11-3 (GND) CN11-5 (+5 ±0.5 V dc) & CN11-6 (Signal GND) CN 1-1 (+40 ±4 V dc) & CN1-3 (GND) CN 1-2 (+40 ±4 V dc) & CN1-3 (GND) CN 1-5 (+5 ±0.5 V dc) & CN1-6 (Signal GND) If the voltages are not correct, replace the power supply unit. If the failure remains, replace the main logic board and sub logic board. Note: When replacing the main logic board, always perform the "Bidirectional print adjustment" on page 4-3 and the "Printhead-to-platen gap adjustment" on page 4-2. 2-16 Service Manual