Lenovo ThinkCentre M55, Hardware Maintenance Manual

Page: 78 / 388

No-beep symptoms
Symptom/Error FRU/Action
No beep during POST but computer works correctly. System board
No beep during POST. 1. See “Undetermined problems” on page 76.
2. System Board
3. Memory Module
4. Any Adapter or Device
5. Riser Card
6. Power Cord
7. Power Supply
POST error codes
Each time you power-on the system, it performs a series of tests that check the operation of the system
and some options. This series of tests is called the
Power-On Self-Test , or POST . POST does the following
operations.
• Checks some basic system-board operations
• Checks the memory operation
• Starts the video operation
• Verifies that the diskette drive is working
• Verifies that the hard disk drive is working
If the POST finishes without detecting any problems, a single beep sounds and the first screen of the
operating system or application program appears.
If the POST detects a problem, an error message appears on the screen. A single problem can cause several
error messages to appear. When you correct the cause of the first error message, the other error messages
probably will not appear on the screen the next time you turn on the system.
In the following index, X can represent any number.
POST Error Code FRU/Action
162 Configuration error Select the default settings in BIOS. See Chapter 6
“Diagnostics, Test and Recovery Information” on page 47.
164 Memory Size Error 1. Run the Extended Memory Diagnostic tests
2. Replace memory modules
166 Boot Block Check Sum Error 1. Perform a flash update to update the BIOS level
2. System board
167 No Processor BIOS update found 1. Run Setup. Check Stepping level for the BIOS level
needed, then perform the flash update.
2. Replace the microprocessor
175 Primary Copy of Secure Data is damaged 1. Run Setup and select default settings
2. System board
176 The System has been tampered with 1. Covers were removed from the computer
72
Hardware Maintenance Manual