Oki OKIFAX 5750 Maintenance Manual page 827

3.7.9 RAM NG
9: RAM NG
Check RAM1 solderling.
Check appearance of
G4A board.
Check DRAMOE1_N
signal level at
RAM1-29 pin.
Waveform of pins 14, 31,
13, 2 of RAM1 are similar
to Figure 3.7-8.
Replace G4A board.
41285901TH Rev.3
DRAM read/write test result is NG.
Bad
Good
Bad
Good
High
Low
No
Yes
Re-solderling
Modify bad point
Replace IC1
Replace RAM1
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