2.4  System Board Troubleshooting  2  Troubleshooting Procedures 
Satellite A50S/TECRA A3X Maintenance Manual (960-534)                [CONFIDENTIAL]  2-17 
Check 3  The IRT checks the system board. When the IRT detects an error, the system 
stops or an error message appears. 
If one of the following error messages (1) through (17), (23) or (24) is 
displayed, go to Procedure 4. 
If error message (18) is displayed, go to the Keyboard Troubleshooting 
Procedures in Section 2.7. 
If error message (19), (20) or (21) is displayed, go to the 2.5” HDD 
Troubleshooting Procedures in Section 2.6. 
(1)  PIT ERROR 
(2)   MEMORY REFRESH ERROR 
(3)   TIMER CH.2 OUT ERROR 
(4)   CMOS CHECKSUM ERROR 
(5)   CMOS BAD BATTERY ERROR 
(6)   FIRST 64KB MEMORY ERROR 
(7)   FIRST 64KB MEMORY PARITY ERROR 
(8)   VRAM ERROR 
(9)  SYSTEM MEMORY ERROR 
(10)  SYSTEM MEMORY PARITY ERROR 
(11)  EXTENDED MEMORY ERROR 
(12)  EXTENDED MEMORY PARITY ERROR 
(13)  DMA PAGE REGISTER ERROR 
(14)  DMAC #1 ERROR 
(15)  DMAC #2 ERROR 
(16)  PIC #1 ERROR 
(17)  PIC #2 ERROR 
(18)  KBC ERROR 
(19)  HDC ERROR 
(20)  HDD #0 ERROR 
(21)  HDD #1 ERROR 
(22)  TIMER INTERRUPT ERROR 
(23)  RTC UPDATE ERROR