Lexmark T620 Service Manual page 33

4069-5XX/7XX
Error Code
940 Service LV
Power Supply
947 PQET Error
948 PEL Clock
Error
949 Delay Line
Calibration
Failure
953 - 954
NVRAM Failure
955 Code CRC
<loc>
956 - 959 System
Board
Action
The low voltage power supply zero crossover test failed.
• Check the LVPS for correct installation. Ensure that
the connector on the LVPS assembly is firmly seated
with the connector on the interconnect card connector.
• This error can be caused by a noisy AC input power
source.
• Check to make sure the correct LVPS has been
installed.
• If all the above are correct, replace the LVPS
assembly.
Indicates that the PQET RAM test was incomplete or a
PQET RAM test busy failure occurred. Replace the
system board.
Indicates the PEL clock check failed. Replace the
system board.
Indicates a delay line calibration failure. Replace the
system board.
System board failures.
953 NVRAM Chip Failure
954 NVRAM CRC Failure
Replace system board.
Code ROM and NAND failed CRC check
*<loc> = For a ROM CRC failure, the location (loc) will be
a failing block or (Bn).
*<loc> = For a NAND CRC failure, the location (loc) will
be a failing page or (Pn).
Replace System Board.
Error codes 956 thru 959 are system board failures.
*956 = Processor Failure
*957 = ASIC Failure
*958 = SRAM Failure
For any of these failures, replace the system board.
Diagnostic Information
2-5