
Dell Precision™ T3500 Service Manual--LED Codes
file:///C|/Biz%20Client/2015/NewBalance/Info%20Dev%20Root/New%20Balance/SM/A00/EN/Source/diags.htm[5/15/2015 11:40:58 AM]
Diagnostic Light Codes
Four (4) single color lights are incorporated on the front control panel to serve as a diagnostic aid for troubleshooting systems
exhibiting No Post/No Video symptoms. The lights do not report runtime errors.
Diagnostic LED Patterns
LED pattern (1234) LED Description
State description
1 - Off
2 - Off
3 - Off
4 - On
BIOS checksum failure detected; system is in recovery mode.
1 - Off
2 - Off
3 - On
4 - Off
Possible processor failure.
1 - Off
2 - Off
3 - On
4 - On
Memory failure.
1 - Off
2 - On
3 - Off
4 - Off
Possible expansion card failure.
1 - Off
2 - On
3 - Off
4 - On
Possible video failure.
1 - Off
2 - On
3 - On
4 - Off
Diskette drive or hard drive failure.
1 - Off
2 - On
3 - On
4 - On
Possible USB failure.
1 - On
2 - Off
3 - Off
4 - Off
No memory modules detected.
1 - On
2 - Off
3 - Off
4 - On
System board failure.
1 - On
2 - Off
3 - On
4 - Off
Memory configuration error.
1 - On
2 - Off
3 - On
4 - On
Possible system board resource and/or system board hardware failure.