Diesel Place banner
1 - 20 of 54 Posts

·
Banned
Joined
·
6,537 Posts
Discussion Starter · #1 ·
I swapped in 2-145A alts, on my dual alt settup. The old 105's removed. I get 14.3V at idle with the battery light on, and DIC message "battery not charging". The light goes out over 1400 rpm. Surely 14.3 V is more than enough to kill that circuit? I assume it is a voltage measurement that triggers the light.

Despite my best efforts, I shorted the battery block when disconnecting the system. May have something to do with it.

I plan to upgrade the wiring to 4 or 2 gauge at some point, don't see how that could be the problem.
 

·
Registered
Joined
·
1,466 Posts
What is the voltage @ 1400 rpm?
 

·
Registered
Joined
·
1,035 Posts
What voltage do you get over 1400 rpm?
 

·
Registered
Joined
·
1,466 Posts
Use your jumper cables to bring battery voltage to the drivers door. (Makes your legs longer, LOL)
 

·
Registered
Joined
·
1,466 Posts
Check fuses KB. If you have a trouble light check them all. May just be a DIC problem
 

·
Registered
Joined
·
1,466 Posts
I plan to upgrade the wiring to 4 or 2 gauge at some point, don't see how that could be the problem.
Battery cables should be 2 gauge, OEM. 1/0 would be next size up. I plane to go to 1/0 or 2/0 my self.

FWIW.
 

·
Registered
Joined
·
1,466 Posts
14 left, 4 right.
 

·
Registered
Joined
·
29 Posts
Despite my best efforts, I shorted the battery block when disconnecting the system. May have something to do with it.
It sounds to me like you have damged the fusible link between the alternator and the battery (the charge lead). You should get out a multimeter, flip it to ohms, and measure between the end that connects to the alternator and to the battery (it doesnt matter which one because they are in parallel) If you have over a few ohms then you could have a problem. If you have over 20, or 40 then you absolutely have a problem.

The short you mentioned earlier could have just damaged the cable, making high resistance which would make the computer not see the batteries charge, but once the alternator starts cranking out more amperage (at higher rpm) it is probably sending enough juice to make the computer register. Also, the high output alternators could have enough power to damage the factory fusible link just under normal duty because they can put out more than the link is rated for. Even if this isnt the fix, you should change the cable out.
 

·
Banned
Joined
·
6,537 Posts
Discussion Starter · #13 ·
Checked all fuses on th dr side. Found 2 hdlp cb's blown, which answered my headlight issue (another story).

The only fusible link is on the wire from the no 1 alt to the battery block. That wire checks at .1 ohm motor off, 2.2 Ohm running. The battery cables have no links I can find.

Still stumped. The weird thing to me is, either one of these should be able to power the system alone. Time to check for codes.
 

·
Registered
Joined
·
1,466 Posts
Are the Dual Alts factory installed?
Are the present Alts OEM?
Was the engine running when the short occurred

If the Alts were added or changed post OE, they may be ReMans.

Do you hava a clamp-on amp meter?
 

·
Banned
Joined
·
6,537 Posts
Discussion Starter · #15 ·
No codes

Pulled the 4 pin connectors on each alt. Showed discharging state, about 10 V, light on. Expected

Plugged in number 1 alt. Shows charge, light out

Unplugged number 1 alt, plugged in number 2, shows same charge (14.5v), light on

Totally baffling. FYI, the number one alt connector has 2 wires, the number 2 alt has just one.
 

·
Banned
Joined
·
6,537 Posts
Discussion Starter · #16 ·
Are the Dual Alts factory installed?
Are the present Alts OEM?

If the Alts were added or changed post OE, they may be ReMans.

Do you hava a clamp-on amp meter?
Factory duals, these are both new, but each comes from a different source. The one that is throwing the light came from Checker (a place I hate). I wonder if there could be a diiferent TR in some of these that is a compatability issue.
 

·
Registered
Joined
·
1,466 Posts
Disconnect one alt and check operations.

Try each alt by its self.
 

·
Registered
Joined
·
1,466 Posts
Will this help? It for the '03.

 
1 - 20 of 54 Posts
Top