GS WorldView Presents an Online Exclusive [::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::] [: Apple IIE Repair Guide :] [::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::] [: Part 2 of 5 :] [::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::] Written By: Double Density [::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::] Part II - Run Problems ---------------------- 1) Disk drive will not read (I/O error or disk just runs on and on) Probable Defect: Remedy: ---------------- ------- a) Bad Disk Replace Disk b) Wrong DOS Try another disk c) Disk not seated Reseat disk d) Read head not reading Replace head e) Cable loose or bad Reseat or replace cable f) Bad chip on analog card Replace Analog Card 2) Disk drive will not write (read is OK) Probable Defect: Remedy: ---------------- ------- a) Write protected Remove tab b) Protect switch bad Replace switch c) Disk not formatted format disk d) Cable bad or loose Check/Replace cable e) Corroded connectors Clean connectors f) Bad 74LS125 replace (analog card) g) Bad CA3146 replace " " h) Bad MC3470 replace " " i) Bad ULN2003 replace " " j) Bad Write head replace k) head alignment off realign head 3) Disk reads or writes occasionally Probable Defect: Remedy: ---------------- ------- a) Cable corrosion clean connector pins b) Connector corrosion clean connector pins c) noise interference good luck d) disk tracking off realign head 4) Occasionally keyboard locks up and computer locks up Probable Defect: Remedy: ---------------- ------- a) Program error debug program b) no keyboard out put coming later c) bad RAM chip replace and test d) bad MMU chip replace and test e) bad CPU at C4 replace and test This concludes the second part in this series.