Xerox WorkCentre Pro 423 Service Manual page 211

Chain Function
153 153 CODEC
153 155 G/A
153 161 G4 Loop Back
253 100 DRAM
253 101 DP-RAM
253 102 ROM
253 103 G/A DPMC1
253 104 CODEC & G/A RCNV
253 105 MODEM Register, RAM Check
253 106 MODEM Loop Back Test
253 107 EEPROM
253 110 Loop Back(ISDN ch0)
253 111 Loop Back(ISDN ch1)
WorkCentre Pro 423/428
Description Object PWB
G4M1
G4M1
G4M1/ICM
G3M2
G3M2
G3M2
G3M2
G3M2
G3M2
G3M2
G3M2
G3M2/ICM
G3M2/ICM
03/02
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How to use the Diagnostic C/E Mode
CHAPTER 2 TROUBLESHOOTING