Fully test the system
This post is part of a series describing the generic, high-level troubleshooting process.
Previous Posts:
What is Troubleshooting?
Simplified Troubleshooting Overview
Step 1. Understand the correct inputs and outputs of the “black box.”
Step 2. Determine which output(s) are incorrect.
Step 3. Figure out which input(s) affect that output(s).
Step 4. Verify that those inputs are as expected.
Step 5. Analyze the path(s) from input(s) to output(s).
Step 6. Check all connections.
Step 7. What are the devices in those path(s) that change the data?
Step 8. Eliminate the devices that could not cause this output.
Step 9. Test the remaining devices.
Step 10. Repair/Replace faulty device(s).
Step 11. Fully test the system.
Now that all of the issues are (hopefully) fixed, the entire system needs to be fully tested.
Test every condition, every input combination. Do not skip anything. It is possible that your “fix” caused other issues, or even that there were more issues than you found the first time around.
If everything is not working properly, start over at step 1 and repair the newly found issues. Take into account that the work that you did could have caused the new problem(s). This could help you find the issue more quickly.
This is the final post in this series. Hopefully it was helpful for you.