Charging battery

[duck76073]

Battery will not charge on vehicle. Removed battery and put on bench charges ok. Charging on vehicle the negative post gets extremely hot and discharge the battery. Help

 

[ljjhouser]

Sounds like a poor or high resistance ground while on vehicle - maybe.

 

[fiddlearound]

Check your engine ground.

 

[Ken45101]

If the post gets hot, it is probably a dirty connection on the post.

 

[RalphVa]

Probably your negative ground, but I'd check the ignition switch, too.

My 2025R had a small electrical leak in the starter relay that cooked the ignition switch and caused corrosion on both battery terminals.

 

[duck76073]

Thanks a lot for all the comments

 

[duck76073]

The battery is on my Chevy pickup. The charger negative terminal is what gets hot and shows to be discharging after 30 minutes.

 

[ROUSTABOUT]

Voltmeter? Battery should be 12.5 0r so and should be 13+ when runnimg. Leave your battery un hooked for a while and see if it holds a charge. 12.87 is what my meter reads on a good battery. It should be the same, hours later.

Don't disconnect battery while engine is running on the newer vehicles. That's a no no. Old ones it's okay to do that, new ones not. By old ones I mean before fuel injection.