Ok so we have a 1996 dodge Ram 1500.... It won't start on it's own, it will however start from a jump at the starter. Abs and airbag lights are on, there is no defrost or heat nothing works. Checked the fuses they are fine checked the battery it's fine. We recently changed the water pump it ran for a day now it's doing this.... did a diagnostics test on it and these are the codes it gives.... 12,43,21,43,43,25,
Now I know what they mean but we are still at a loss on what might be causing these issues. Like I said battery is fine fuses are fine and since of course it Jumps at the starter coil is fine.....

Any thoughts or ideas would help.....

 

Check your battery cables. I had kind of the same trouble. Changed the starter 3 times before I actually started it, by jumping it at the starter. lol Still took me several hours ro realize it's probably the cable from battery to starter.

 

"It won't start on it's own". OK but what does it do? Does it turn over without starting, or does it do nothing when you turn the key, or does it click? Have you checked the starter relay?