1994 F800 Chip Truck no power from batteries.

[SouthernTreesNewbie]

Alright team, let me tell you the problem, what I have checked and what I have fixed. Then please share your knowledge because I am out of ideas.
Problem: go to turn the key, absolutely nothing, no bings, bongs, lights, all silent and dark.
What have I checked and replaced: started at the batteries they were older and didn’t keep the charge from the trickle charger so I replaced them. Cleaned all connections before reinstalling. Nothing happened. I tracked the lines from the batteries, made sure ground was right and connection was good, same with power. Both are well connected and no corrosion. Checked my fuses, none were busted, but I did replace some of the crustier older ones with new ones. Still nothing. Final step was the ignition switch, not the cylinder but the actual connector. Pulled it apart and it was very dirty, cleaned harness with electrical cleaner and put the new switch in. Nothing has worked. Still zero response. Thank you in advance.

 

[johninky]

see if the ign sw is receiving power.

 

[user 159780]

Retrace the steps above starting with the battery, but use a meter to trace the voltage up to the ignition switch and beyond.
Since I was unable to locate a free wiring diagram (on line), for your truck, suggestions are limited.

 

[Junkyard78]

Sounds a lot like a ground issue to me if you have zip. Remove the grounds from the frame, engine and anywhere else you have them and thoroughly clean them. If you know how to use a meter test your cables for voltage drop as well as trace the voltage from the battery cable on up. Some of those medium duty trucks run power through a relay that looks like a Ford solenoid, might have an issue there.

What engine does it have in it? Did you miss a wire when you replaced the batteries? Sometimes there’s an additional hot that goes on with the positive. Does the insulation on the cables have any swollen spots like it’s corroded internally? Also try a jumper cable on the ground side from the battery to the frame and see what that gets you. It’ll tell you if the ground cable is bad.

Check those things and let us know what you find.

 

[SouthernTreesNewbie]

Thank you for the advice. I finally got a morning to troubleshoot. Metered the batteries, they are good. Traced the main battery ground and it is cleaned and metered good. Traced the main hot to the starter, no drop in voltage to the starter. The ground at the starter is good as well. I am having trouble tracking the hot wires coming off the starter so I will dig back into that to see where it goes. I did meter all the fuses and found that the large circular one wasn’t completing a circuit on its own. So I am off to replace it and hope this is the fix. If not I will continue to trace the power lines through the truck.

 

[SouthernTreesNewbie]

Well not the fuse, traced power back to the ignition tumbler. That seems like the most likely culprit. I will be pulling the steering wheel off to get it replaced. Any other tips, or ideas? Thanks for all the help.