Home » Lexmark Manuals » Dot Matrix Printers » Lexmark 4227 » Manual Viewer

Lexmark 4227 Service Manual - Page 14

Voltage, ground, and continuity readings, Voltage readings, Ground checks - 100

UPC - 734646117104

Add to My Manuals
Save this manual to your list of manuals

Page 14 highlights

4227-300 Voltage, ground, and continuity readings Voltage readings All DC voltages must be within +5% through -10% of the values to be considered correct. Unless stated otherwise, all connectors should be connected normally when a voltage measurement is done. When a "line voltage" measurement is to be done, the voltage on United States and Canada machines should be between 100 V ac and 127 V ac. On World Trade machines, the voltage is according to each country's specification. Ground checks To check for a correct ground, measure the voltage between the ground and a known good voltage source. The voltage measurement must be the same as the source voltage to consider the ground is correct. Continuity measurements may be used to check grounds; however, be sure to measure to a known good ground using the lowest ohms scale and check for zero ohms. WARNING: Always unplug the power cord before doing any continuity measurement. Continuity readings When measuring continuity, be sure no back circuits affect the measurement. If necessary, unplug connectors to remove any back circuits. Zero the ohm range on the lowest scale (X1). An open circuit will read infinity. A circuit with correct continuity will read zero ohms. 1-2 Service Manual

Section	Page
Table of contents	3
Safety information	7
Preface	12
1. General information	13
Description	13
Voltage, ground, and continuity readings	14
Voltage readings	14
Ground checks	14
Continuity readings	14
Maintenance approach	15
Options	15
Tools	15
Abbreviations	16
Using the operator panel	17
Using the function menus	18
Setting printer functions	19
Overview of function menus	20
Buttons	22
Lights	23
2. Diagnostic information	25
Start	25
Error indication table	25
Symptom tables	27
Abnormal Indications	28
Abnormal print operation problems	28
Auto Sheet Feeder problems	29
6XX Error indications	29
Paper feed problems	30
Operator panel problems	32
Power Problems	32
Print quality problems	33
Ribbon feed problems	34
Service checks	35
Auto Gap service check	35
Theory of operation	35
Auto Sheet Feeder (ASF) service check	37
Auto Sheet Feeder principles of operation	37
Carrier drive service check	39
Intermittent problem service check	40
No print or abnormal print service check	43
Operator panel service check	44
Paper feed service check	45
POST service check	48
Power failure service check	49
Print quality service check	51
Print wire drive failure service check	52
Ribbon drive service check	54
Tractor 2 service check	55
63D Tractor 2 HP error	55
Tractor 2 installed, but not shown in User Menu	57
Paper feed problems	58
3. Diagnostic aids	59
Power-On Self Test (POST)	59
Hex trace mode	60
Hex trace mode sample	60
Interface selection	61
Operation with the top cover removed	61
Service Menu	61
Button Test	62
Factory Setting	62
Printhead Bank	62
Jam/PSet Sensor Test	62
Impact force	62
Log clear	62
Print Test	63
Other print tests	63
Error log	63
4. Repair information	65
Handling ESD-sensitive parts	65
Adjustments	66
Printhead installation adjustment	66
Printhead-to-platen gap adjustment	66
Printhead-to-platen gap left and right	66
Printhead-to-platen gap electronic setting	67
Bidirectional print adjustment	67
Removals	69
Top cover removal	69
To Reinstall:	71
Auto Gap motor removal	72
Auto Sheet Feeder gears removal	73
Auto Sheet Feeder pick-up roller removal	74
Belt tension pulley plate assembly removal	75
Base assembly removal	75
Carrier removal	76
To reinstall:	78
Carrier motor assembly removal	79
To reinstall:	79
Carrier plate removal	80
Label jam removal	80
Lower feed roller removal	81
To reassemble:	84
Lower pinch roller removal	85
Main logic board removal	85
To reinstall:	85
Memory Module removal	86
Operator panel assembly removal	86
Paper Empty sensor/TOF sensor removal	86
To replace the TOF Sensor Flag:	88
Paper feed motor removal	89
To reinstall	89
Paper guide removal	89
Paper guide/platen assembly removal	89
Paper Select lever removal	89
Paper Select sensor removal	90
Paper separator removal	91
Power supply removal	93
Power supply fan removal	93
Print unit removal	93
To Reinstall	95
Printhead removal	96
To reinstall	96
Printhead cables removal	97
To reinstall	97
Ribbon drive motor assembly removal	98
Right side frame removal	99
To reassemble	101
Sub logic board removal	101
To reinstall	101
Upper feed roller removal	102
5. Preventive maintenance	103
Lubrication	103
Specified lubricants	103
Lubrication points	104
Oil	104
Grease	104
6. Locations and connectors	105
4227-300	105
Main Logic Board Connectors	106
Operator panel connectors	107
Component locations	108
Component location illustrations	109
Component location illustrations (Continued)	110
Signal connections	111
Main Logic Board<-->Paper Empty & TOF Sensors	113
Main Logic Board<-->Carrier Motor Cable #1	113
Main Logic Board<-->Paper Feed Motor	113
Main Logic Board<-->Tractor 2 DIN	114
Main Logic Board<-->Carrier Motor Cooling Fan	114
Main Logic Board<-->5 V dc Power	114
Main Logic Board<-->Operator Panel	115
Main Logic Board<-->Tractor PSet & Jam Sensors	115
Main Logic Board<-->Ribbon Motor	116
Main Logic Board<-->Auto Gap Motor	116
Main Logic Board<-->Serial Board	116
Serial Board<-->Serial Cable	117
Sub Logic Board<-->Printhead	118
Operator Panel Board<-->Ribbon Cover Sensor	118
Tractor 2 cable connectors	119
Connector block diagram	120
7. Parts catalog	123
How to use this parts catalog	123
Assembly 1: Covers and operator panel	124
Assembly 2: Paper feed	126
Assembly 3: Carrier	128
Assembly 4: Base and electronics	130
Assembly 5: ASF side frame/covers	132
Assembly 6: ASF roller/support	134
Assembly 7: Tractor 2 option	136
Index	139
A	139
B	139
C	139
D	139
E	139
F	139
H	139
L	139
M	139
O	139
P	139
R	139
S	140
T	141
U	141