another no power/ no lights question

[kcbbqguru]

I went to drive my truck sunday, turned the key, and dash light went out, no power
checked batteries with load tested and tested fine. Had the wife come out to turn key, took the jumper from
front battery to rear battery and go power to dash, and would even turn engine but not enough power to start.
put battery post back on and nothing?
thanks

 

[Barrman]

How did you load test your batteries? You either have a bad battery, loose or corroded connections or now that you tried to turn the engine over with the smallest wire from the batteries. A burned fuseable link.

Start with checking the batteries separately with a real carbon pile type load tester.

 

[kcbbqguru]

thanks Barrman,
It's amazing what 2 brand new batteries will do to start a truck, old ones had bad cells, now need to trace the why the headlights not working!

 

[MarcusOReallyus]

not on the trace the headlights not working!

English, please?

 

[corelokt]

If it comes back, suspect where the fuse box bolts together at the firewall. Ignition switch too.

 

[Abbylind]

Whats a truck sundae? Extra lug nuts on top...