Oki ML421 Maintenance Manual - Page 102

Troubleshooting flow chart

Get Oki ML421 PDF manuals and user guides View all Oki ML421 manuals
Add to My Manuals
Save this manual to your list of manuals

Page 102 highlights

Oki Data CONFIDENTIAL 6.5 Troubleshooting flow chart 1 Power is not supplied. Is the AC cable connected correctly? Yes No Connect the AC cable correctly. Is fuse F1 on the transformer assy/or F1 on the Power Supply Board blown? No Yes Replace fuse (with same type and rating). Remedied? No Yes End Does DC + 50V out? No Yes Remove Printhead. (Turn power off, then on.) Remedied? No Yes End Replace carriage cable or ribbon feed mechanism. Remedied? No Yes End Replace Control Board. Remove CN3 on Power Supply Board. Measure for any short circuits between + 5V, + 50V, +12V, -8V, 0V in CN2 of Control Board. Any short circuit? No Yes 42113901 Rev.2 102 /

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
42113901
Rev.2
102 /
Oki
Data
CONFIDENTIAL
6.5
Troubleshooting flow chart
1
Power is not supplied.
Is the AC cable connected correctly?
Yes
No
Connect the AC cable correctly.
Is fuse F1 on the transformer assy/or F1 on the Power Supply Board blown?
No
Yes
Replace fuse (with same type and rating).
Remedied?
No
Yes
End
Does DC + 50V out?
No
Yes
Remove Printhead. (Turn power off, then on.)
Remedied?
No
Yes
End
Replace carriage cable or ribbon feed mechanism.
Remedied?
No
Yes
End
Replace Control Board.
Remove CN3 on Power Supply Board.
Measure for any short circuits between + 5V, + 50V, +12V, -8V, 0V in CN2 of Control
Board.
Any short circuit?
No
Yes