Help no tach, check engine light, wait to start

[bjorkmae]

I have a 95 3500 5.9 and the check engine light won't come on, the wait to start light doesn't come on, and of course no tach. Sometimes these things will work some times not, if they do work its only for the first few minutes. I have alreadty checked all fuses, relays, and connections. I can just barely here the computer humm when the key is in the on position but the engine isn't running. Any ideas??

 

[Black dawg]

is the alt charging?

 

[bjorkmae]

Only when everything else works for a few minutes. The alternator has been replaced too as well as new batteries.

 

[bjorkmae]

As an update, I got the problem fixed with a used computer. Cost $150 shipped to my door with 3 day UPS. Thought I would post the update since lots of people seamed to have the same problem in the past and never posted an update for a fix. Plus lots of posts said it was the engine speed sensor but I knew that couldn't be it because I couldn't even get the wait to start light to come or check engine light to come on. Seams to have fixed the problem for over a week now so I am confident it was the problem. Now if I could just get OD to work. I replaced my bad TPS as the old one tested horribly bad and the new one tests good but still no OD.The TQ lockup works fine but no OD.