2004 silverado 5.3l alternator not charging

[2400hd]

So I bought this truck, (2004 Silverado 1500 5.3l), it needed fuel system work so it couldn't be driven on initial sale, I did the work and got it started, yet doesnt charge, so i swapped alternators, still not charging, has power at the large power lug, grounds are all fine, but no power at the pins on the small electrical plug, i was told they have a exciting power wire from the ignition switch to the dash battery warning light, then out to the alternator, do they have a charging system fuse ? Where can I get a wiring diagram? Thanks for any info,

Edited November 10, 2024 by 2400hd

[richard wysong]

Fuse in underhood fuse box

[2400hd]

Just now, richard wysong said:

Fuse in underhood fuse box

Thanks, have a look when im off work and report back,

[2400hd]

So looked at a post from a different website that said to look at the IGN SEO AND IGN E fuses, they both have current running through them with the key on, and aren't blown, are these the correct fuses ? the owners manual doesnt say anything about a charging system fuse that I could find, link to the mentioned website  -  https://www.2carpros.com/questions/2004-chevrolet-silverado-alternator-fuse

Edited November 12, 2024 by 2400hd

[Niel04Z71]

Believe me, it’s the instrument cluster that needs rebuilt. I literally replaced everything before I discovered the issue. The cluster puts everything to sleep. There’s no code for it and no diagnostic test will catch it. Contact David Ruberg at Speedometer Guys in Minnesota. It’s all they do. Lifetime warranty and about $70. Sent mine out and had it back in 9 days. His number is (507) 429-4489

[richard7rd]

On 11/10/2024 at 4:00 AM, 2400hd said:

So I bought this truck, (2004 Silverado 1500 5.3l), it needed fuel system work so it couldn't be driven on initial sale, I did the work and got it started, yet doesnt charge, so i swapped alternators, still not charging, has power at the large power lug, grounds are all fine, but no power at the pins on the small electrical plug, i was told they have a exciting power wire from the ignition switch to the dash battery warning light, then out to the alternator, do they have a charging system fuse ?Scratch cards are a quick gambling website Where can I get a wiring diagram? Thanks for any info,

So yeah, on your 2004 Silverado 1500 with the 5.3L, the alternator needs that exciter wire (usually the L terminal) to tell it to start charging — and if there’s no power there, it’s not gonna do squat, even with a brand new alternator.

Edited May 19, 2025 by richard7rd