DC power cable
DC power level
Electrical noise
Interface cable connection
Terminating resistors
Drive selection address
Plug setup
System cables
System diagnostic test
Intermittent or nonfatal errors
106
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Table 6.2
Item
Check that the power cable is correctly connected to the disk drive and
power supply unit.
Check that the DC voltage is within the specified range (±5%).
Check that +5V DC supply is from 4.75 to 5.25V DC.
For NC model, check the voltage between pin 36 and 76 of the SCSI
connector.
For NP model, check the voltage between pin 3 and 4 of the power
connector.
Check that +12V DC supply is from 11.4 to 12.6V DC.
For NC model, check the voltage between pin 1 and 2 of the SCSI
connector.
For NP model, check the voltage between pin 1 and 2 of the power
connector.
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.
Check that the SCSI interface cable is correctly connected between the
disk drive and controller.
For a daisy chain connection, check the terminating resistor on the last
disk drive only. For a star-burst connection, check that the terminating
resistor is correctly mounted on all disk drives.
Check that the disk SCSI ID is set correctly.
Check that the jumpers on the PCBA are set so that the disk drive and host
computer operate normally. See Section 5.3.
Check that all system cables are connected correctly.
When possible, execute the system level diagnostic routine as explained in
the host computer manual. This gives a detailed report of a possible fault.
Check the AC voltage from the power supply. Check the DC voltage level
at the power connector for the HDD.
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 HDD. If replacing the HDD does not eliminate the
error, the removed HDD is probably not faulty. To continue error
analysis, refer to the hardware and software manuals supplied with the
system.
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System-level field troubleshooting
Recommended work
C141-E270