Codes P0621 & P0622 [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: Codes P0621 & P0622


gtguy67
03-29-2005, 08:45 PM
Was driving my 04LLY when the "BATTERY NOT CHARGING" came on in the DIC and the battery light illuminated. The ampmeter dropped to about 9, then after a while rose back to ~14. I'd gather the problem is in the alternator, but I did a scan with the Predator and had the above codes, anyone have an idea what they are? The truck has 23k on it and I'm headed to the dealer o'dark thirty to see if they can get me on the road...

briano
03-29-2005, 10:30 PM
Was driving my 04LLY when the "BATTERY NOT CHARGING" came on in the DIC and the battery light illuminated. The ampmeter dropped to about 9, then after a while rose back to ~14. I'd gather the problem is in the alternator, but I did a scan with the Predator and had the above codes, anyone have an idea what they are? The truck has 23k on it and I'm headed to the dealer o'dark thirty to see if they can get me on the road...
P0621 Generator Lamp "L" Control Circuit Malfunction
P0622 Generator Field "F" Control Circuit Malfunction

I know that doesn't help you much, but will help the tech looking at it.
Looks to point to the alt like you think