Service manual

iv Sun Ultra 2 Series Service Manual • July 1998
3.2 Pre-POST Preparation 3-2
3.2.1 Setting Up a Tip Connection 3-2
3.2.2 Verifying the Baud Rate 3-4
3.3 Initializing POST 3-4
3.4 Maximum and Minimum Levels of POST 3-6
3.4.1 Diag-Level NVRAM Variable Set to max 3-6
3.4.2 Diag-Level NVRAM Variable Set to min 3-11
3.5 POST Progress and Error Reporting 3-12
3.6 Bypassing POST 3-14
3.7 Additional Keyboard Control Commands 3-14
3.8 System and Keyboard LEDs 3-15
3.9 Initializing the Motherboard POST 3-15
4. Troubleshooting Procedures 4-1
4.1 Power-On Failure 4-1
4.2 Video Output Failure 4-2
4.3 Hard Drive or CD-ROM Drive Failure 4-3
4.4 Power Supply Test 4-4
4.5 DSIMM Failure 4-8
4.6 OpenBoot PROM On-Board Diagnostics 4-10
4.6.1 Watch-Clock Diagnostic 4-11
4.6.2 Watch-Net Diagnostic 4-11
4.6.3 Watch-Net-All Diagnostic 4-12
4.6.4 Probe-SCSI and Probe-SCSI-All Diagnostic 4-13
4.6.5 Test alias name, device path, -All Diagnostic 4-14
4.6.6 UPA Graphics Card Diagnostic 4-15
5. Safety and Tool Requirements 5-1
5.1 Safety Requirements 5-1
5.2 Symbols 5-1
5.3 Safety Precautions 5-2