Hi All,

I'm new here and need a little help. I tried searching for similar post but didn't have any luck.

So today I was driving on the highway and my truck seemed like it hiccuped, all the warning lights flashed for a second. After that I noticed the amp gauge was going down. It stalled on me a few times before I could get it to a shop to have battery and alternator checked. The battery was low but alternator needed to go.

I swapped that out and had battery charged up. So amps are better ( above 10) but I feel like it shudder be higher.

My question is what could have caused this and should I check anything else out?

Recently I just changed out spark plugs, that's the only maintenance done lately.

It's a 99 with 5.9 360. About a 130,000 miles.

Thanks for the help in advance.

 

Alternators get old and die. Voltage across the battery posts should read about 14.2 with engine running.....The oem neg battery post connector is pretty weak.. you might consider changing it. Or at least inspect and clean both battery posts and connections with a wire brush. Welcome to DF!

 

welcome to df.

the voltage regulator is built into the pcm, which sucks.

your voltage (not amps) gauge should be reading about 14 with engine running.
battery voltage should be about 14 with engine running, about 12-13 with engine off.
something is still wrong. at 10 volts, the battery will slowly discharge.

the alternator can be tested outside the truck (at the parts store) to verify its capable of putting out 14+ volts and some number of amps (100+)

 

I was thinking amps was wrong right after I posted it, haha. Long day.

Well I guess it's back to have it tested again. The battery isn't new so maybe there's a chance it's bad. I can't really remember if te volt gauge was at 14 before all this happened.

I think I'm going to try and find a PCM at a salvage yard and swap out the negative cable.

Thanks for the tips.

 

Ok, battery is dead. I checked under the hood a little bit and noticed the cable leading to the battery/ fuse box is split and corroded a little.

What is that cable actually called? I tried searching for one but had no luck.

 

its just a battery cable. big black one running to the ground location, and big red one going to the fuse box. i don't recall what type end is on the positive cable at the fuse box, but just match color, length, end type and replace it.

unless the cable is broken, or copper exposed, or the battery end is broken and messed up, the cable is probably ok. its big stranded copper, so you can't really hurt its function of carrying power.

 

The copper is exposed a little bit. I can see some corrosion in there. I put in a new battery today since the old ones toast. Still only reading 10-11 volts. I'm guessing it has to be an electrical issue.

When I got a jump start this morning the meter would read 14 when other car was connected to the old battery. I'm going to switch out the negative cable and see if that helps.

Thanks for all the tips, I've had a jeep before and not completely new to Chrysler, but I'm trying to get familiar with it since I haven't found a good mechanic around me yet.

I've found some great info here so I appreciate it.

 

I'm putting money on your alternator also took a crap. There are some threads on replacing brushes etc..and fixing..I don't have the patience. When my alternator started going, I found that if i took my hammer and tapped the alt, it would suddenly start working, (charging) for awhile. Using your alternator to charge totally dead batteries can be harmful to the alt's lifespan.

 

Figured it out. The negative cable coming off alternator had melted and causing it to blow the 140amp fuse. Replaced the cable and tracked down a fuse. Everything's looking good now.

Thanks again for the help.