Run a diagnostic check on aspire3690

The time it takes for a Dell Latitude E6400 to complete a diagnostic boot can vary depending on several factors, including the specific hardware configuration of the computer, the number of diagnostic tests that are run, and the condition of the hardware.
Typically, a diagnostic boot on a Dell Latitude E6400 can take anywhere from 5 to 20 minutes, depending on the specific model and the complexity of the diagnostic tests.
The diagnostic boot process on the Dell Latitude E6400 starts with a pre-boot diagnostic test that checks the basic functionality of the computer's hardware, including the memory, hard drive, and keyboard. This test typically takes only a few minutes to complete.
After that, the system will run a more extensive set of diagnostic tests which include PSA (Pre-boot System Assessment) and ePSA (Enhanced Pre-boot System Assessment) . These tests take longer to complete and check the more in-depth hardware such as the system board, processor, and other internal components.
You can also run an extended diagnostic test that checks all the hardware components of the computer, including the memory, hard drive, and other internal components. This test takes longer to complete and is typically used when the computer is experiencing hardware-related issues.
Please note that the diagnostic boot process can take longer if the computer is experiencing hardware-related issues, and if the computer fails the diagnostic tests, it will stop the boot process and show an error message.

Illuminated Check Engine Lamp with Diagnostic Trouble ...

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May 11, 2015 - Illuminated Check Engine Lamp with Diagnostic Trouble Codes ...P2196, P2197, P0171, P0172, P0174, P0175 or P162F - 2015 Ford Transit.

See if you can run the Pre-boot System Assessment(PSA) diagnostics. To run the PSA+ Diagnostics on this system, perform one ofthe following actions: b> 1) Hold downthe key while pressing the power button. b> 2) Turn onthe system, press at the initial Dell™ logo screen, and select "Diagnostics" from the bootmenu. b> 3) Disconnectthe AC power and remove the battery. While holding down the power button,insert the AC connector into the back of the system. The system then starts andthe message "Diagnostic bootselected" displays. The system then launches the PSA+Diagnostics.
If diagnostics pass then you have a software issue.