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Posted

Hello All;

 

I have a 2004, 5.3L, about 135K.

 

Here's what I know. Relitavly new battery, tested with a meter, off: 12.43, running w/bat. light and message(1):~12.4 / running wo/bat. light or message(2) ~14.5.

 

Step son has been driving for about 5 months. It had been parked for about a year before that. He comes home last night and says the light is on (and Oh, BTW, it has been on for about 2 weeks), Now the message center display says it's not charging. I didn't test it last night because it was raining. Checked this morning and no light or message. Shut it off and checked the battery, ~12.43V. Started it up, again no light, no messsage, tested at about 14.5V. While letting the truck idle, I read a few postings on here and fiddled with the plug to make sure it was getting a good conection. Checked the connections at the battery terminals and the ground could have been tighter. So I shut it off (it had been running for about a half hour still with no light, no message, and about 13.2V on the meter. I wire brushed the terminals and tightened. Started it up and now I have the light and the 'Battery Not Charging' message again. Checked it with the meter again and it's NOT charging. I let it sit for about and hour, but it's still hot and the light and message are still there and it's definatly not charging.

 

I'll check again when it's completly cold and see if this cycle repeats.

 

Is there something that could work when it's cold and then not work when i's hot? I don't just want to replace parts for no reason if i can pin point the problem.

 

Any thoughts or suggestions?

 

Thanks,

 

Posted

We had a Chevy V8 sit for a year and then started using it again, for the first few weeks it was fine, then one night a 30 miinute trip killed the Alternator, We had headlights, and heater running

 

I replaced the Alternator and it was fine after that

 

There is not nuch to the Chevy charging system, everything is inside the Alternator, as long as the heavy red wire is connected to the battery and Alternator and the little plug is in that's it

 

Mine smelled a little burnt, and the windings looked funny

 

It may be heating up and then failing to charge

 

Being a Chevy guy, If its not the battery its the Alternator

 

Good Luck and let us know

 

Joe

 

PS the NCC-74656 kicks the NCC-1701's ASS .....

Posted

We had a Chevy V8 sit for a year and then started using it again, for the first few weeks it was fine, then one night a 30 miinute trip killed the Alternator, We had headlights, and heater running

 

I replaced the Alternator and it was fine after that

 

There is not nuch to the Chevy charging system, everything is inside the Alternator, as long as the heavy red wire is connected to the battery and Alternator and the little plug is in that's it

 

Mine smelled a little burnt, and the windings looked funny

 

It may be heating up and then failing to charge

 

Being a Chevy guy, If its not the battery its the Alternator

 

Good Luck and let us know

 

Joe

 

PS the NCC-74656 kicks the NCC-1701's ASS .....

Joe,

 

Thanks for the reply. I'll wait until the end of the day to see if anyone else has any differing opinions before going for the alternator.

 

As for the NCC's, I couldn't agree more. I only defer to the 1701 because that got it all started (and i saw the originals before reruns), but I agree, Janeway and the crew kick ass.

Posted (edited)

I had to look up what the heck you 2 were talking about....I'm not of that generation apparently!

 

I would get your alternator tested, and then be ready to replace it. That sounds similar to mine. It went on for a couple weeks of sometimes working and sometimes not. Since then, solid 14+ volts all day now!

 

I would also check your battery, you never know. I just had a battery with a bad cell and would cause the door chime to go off without the key! Really weird symptoms, but new battery solved all of that as well.

Edited by sahls01gmc
Posted

Make sure you let us know !!

 

I only say the NCC-74656 is better because of the BORG tech mod for Trans-Warp LOL :)

Posted

Yep, replaced the alternator in about a 45 minutes, no light, no message and guage reads ~14.2. I didn't bother with any further testing.

 

Thanks guys for your input.

 

Looks like I'm done here. Beam me up Scotty........ :D

 

  • Like 1
Posted

That's GREAT!!

Live Long and Prosper :)

  • 2 weeks later...
Posted

Hello again all,

 

Just as a follow up and an FYI:

 

Alternator still working fine with no electricial issues.

 

The FYI part is that about 2.5 - 3 months ago the engin light came on and neither Auto Zone nor O'Reilly could tell why. I still don't know why and I don't know if this is even related, but a few days after changing the alternator it went out. Who knows? ? ? Maybe a coninsidence, maybe not.

 

 

 

 

Posted (edited)

I've never had a GM alternator last 100K without failing in some way. Been that way since my first GM with an alternator in 1969.

My 1998 K1500 alternator didn't even last 30K and the 2002 Yukon about 50K.

Edited by waumo1
  • 5 years later...
Posted
On 4/19/2015 at 5:47 PM, waumo1 said:

I've never had a GM alternator last 100K without failing in some way. Been that way since my first GM with an alternator in 1969.

My 1998 K1500 alternator didn't even last 30K and the 2002 Yukon about 50K.

my 2000 Yukon is just now going out 20yrs and 250k

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