Troubleshooting 101

[CodaMan]

For the last 35 years I have worked as an electrical engineer for the Department of Defense and in those years I have taught 1000’s of military personnel how to troubleshoot aircraft and their systems efficiently, quickly and cost effectively. Whether you are troubleshooting a $100,000,000 aircraft or a $10 toaster the principles are the same. Hopefully these will help you when troubleshooting your Jeep and save you some money at the same time.

1) Never throw parts ($$$) at a problem

2) Understand the function of the system that is failing

3) Determine what has changed or was touched since it worked last and look there first

4) Sit back, think, and come up with a game plan

5) Understand the system failing

6) Is there something I can swap, e.g. 2 injectors, that will give me information?

7) Is there a way to verify a part without replacing it?

8) Go for easy stuff first

9) Understand the system failing

10) Be patient, be thorough and not afraid to ask others.

Good luck and get her fixed.

 

[Chris]

Solid advice! I might also add, that I usually find whenever I'm troubleshooting what seems like an impossible problem to track down, it almost always ends up being an Occam's razor (the simplest explanation is usually the right one) situation.

 

[CodaMan]

Solid advice! I might also add, that I usually find whenever I'm troubleshooting what seems like an impossible problem to track down, it almost always ends up being an Occam's razor (the simplest explanation is usually the right one) situation.

That's for sure and many times it's related to something that just happened or was done.

 

[Chris]

That's for sure and many times it's related to something that just happened or was done.

I agree.

I always encourage people to think about what they were doing before the problem happened.

For instance, if you were removing the intake manifold to change the gasket, and everything was fine before you removed it, but now you have a check engine light on. I would tell them to retrace their steps. The problem most likely did not manifest from out of nowhere, it's most likely because you left something unplugged, installed something incorrectly, or broke a part in the process (i.e. damaged a sensor).

 

[CodaMan]

I agree.

I always encourage people to think about what they were doing before the problem happened.

For instance, if you were removing the intake manifold to change the gasket, and everything was fine before you removed it, but now you have a check engine light on. I would tell them to retrace their steps. The problem most likely did not manifest from out of nowhere, it's most likely because you left something unplugged, installed something incorrectly, or broke a part in the process (i.e. damaged a sensor).

Yes, or high idles after replacing the same gasket

 

[Chris]

Yes, or high idles after replacing the same gasket

Yep, usually it's just a matter of retracing your steps.

Also, figuring out how a specific system works (like you mentioned) and what it has in common with other functions.

For instance. If your turn signals aren't working and the airbag light is on, the one thing those two have in common is the clock spring.