Diesel Wont Start

[Whitehoe]

I have no idea how or what is causing my issue.

i have a 6.5L turbo diesel 96 2500

my batteries are both charged all accessories such as radio, windows, lights all work fine warning lights/wait to start light very very very dim truck shows no volts. Starter turns and then clicks like the batteries are dead. But sometimes out of no where all the lights will come on and truck shows regular volts and starts fine but only very rarely. Really need help figuring this out need to drive truck on friday. Thank you in advance.

 

[1999gmc]

If you are still running the side post battery cables, check for corrosion between the two cables on the passenger side positive cable. And make sure the cables are tight. Sounds like a baf connection and that is a common place. I usually pop the battery cable bolt out and remove the spacer that is in there and wire wheel the bolt, spacer, and wire brush the end of the cable where the bolt goes through.

 

[Whitehoe]

Truck still isnt starting redid all battery connections and tested all the grounds

 

[4x4incountryboy]

How do you know the batteries are good? Just because they read 12 volts, doesn't mean they are good. They can have a bad cell or be weak. Have they been load tested?

 

[Whitehoe]

They were tested at an oreillys

 

[Whitehoe]

i found a way to test if my ignition switch is broken...which it is so im ordering one now and cant wait for it to arrive