Troubleshooting

Symptom Charts/Video - 11

 

 

 

Video

Screen is black, boot tone is present, drive operates, fan is running, and LED is lit

1Adjust brightness on monitor.

2Clear parameter RAM. Hold down <Command> <Option> <P> <R> during startup but before "Welcome to Macintosh" appears.

3Reset Cuda chip. (Refer to The Cuda Chip in Basics for instructions.)

4Reset logic board. (Refer to Resetting the Logic Board in Basics for instructions.)

5Replace monitor cable.

6Remove all DRAM DIMMs and try replacing them one at a time to test. Replace any bad DIMMs.

7Test with known-good monitor. Replace monitor if necessary. Refer to appropriate monitor manual to troubleshoot defective monitor.

8Replace logic board. Retain customer's DIMMs.

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Apple 7200/90, WS 7250/120, 7200/120 manual Video