R914 1 ohm 1/2 watt resistor A2000 (supplies 5 volt to the keyboard)Ī known good mouse and joystick should be used to eliminate them as the source of the problem.U7 Odd CIA (KBdata Pin 39 – KBclock Pin 40) (U300 A2000).If the keyboard is determined not to be the problem, the defect is most likely on the main PCB (A500/A2000 motherboard).If you cannot reset computer, the most probable cause is Q2. The above chips are located on the keyboard. If the caps lock light on the keyboard is flashing when power up, note the number of times it flashes:.RAM on motherboard (Check for excessive heat.If it is too hot to touch, it is bad) (U100 A2000) Substitute a known good power supply to eliminate it as a possible source of the problem.Screen goes from dark grey to light grey but does not display
Restore screen change to light grey, then workbench prompt.Configure memory: If bad, screen green.Temporary exception processing: If artificial exception occurs, screen yellow.AMIGA TROUBLESHOOTER – PART 2: A500/A2000 POWER UP SEQUENCE
