Diagnostics and Maintenance

 

Table 6.2

System-level field troubleshooting

 

 

 

 

Item

 

 

Recommended work

 

 

 

DC power level

 

Check that the DC voltage is within the specified range (±5%).

 

 

For +5V DC, measure the voltage between pin 20 (+5V) of the interface

 

 

connector and the nearest PCA mounting screw (GND) from the

 

 

interface connector, and confirm the value is from 4.75 to 5.25 VDC.

 

 

For +12V DC, measure the voltage between pin 2 (+12V) of the

 

 

interface connector and the nearest PCA mounting screw (GND) from

 

 

the interface connector, and confirm the value is from 11.4 to 12.6 VDC.

 

 

 

Electrical noise

 

Make sure the maximum ripple peak-to-peak value of +5V DC is within

 

 

250 mV and +12V DC is within 250 mV.

 

 

Make sure the high frequency noise (over 20 MHz) is less than

 

 

100 mVp-p.

 

 

 

Drive selection address

 

Check that the disk drive selection address is set correctly.

 

 

 

System cables

 

Check that all system cables are connected correctly.

 

 

 

System diagnostic test

 

When possible, execute the system level diagnostic routine as explained

 

 

in the host computer manual. This gives a detailed report of a possible

 

 

fault.

 

 

 

 

Intermittent or nonfatal errors

 

Check the AC voltage from the power supply. Check the DC voltage

 

 

level at the power connector for the disk drive.

 

 

If the AC voltage level is abnormal or there is a lot of electrical noise,

 

 

notify the user of the error.

 

 

If the DC voltage level is unstable, replace the power supply unit.

 

 

If possible, replace the disk drive. If replacing the disk drive does not

 

 

eliminate the error, the removed disk drive is probably not faulty. To

 

 

continue error analysis, refer to the hardware and software manuals

 

 

supplied with the system.

 

 

 

 

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C141-E219

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Fujitsu MAV2073RC, MAV2036RC manual System-level field troubleshooting