Q: 04 Avalanche "Battery Not Charging" even after new battery, alternator, ecm, and clean cables.

asked by on March 11, 2018

Truck gets a message: "Battery Not Charging" and the battery light comes on. New battery was installed, and the light went away for a few days. It came back on again so the alternator was replaced. The light went away again for a few days. The light came back on so the ECM was replaced and all battery terminals and the ground were cleaned and secured. Today the "Battery Not Charging" light is on, might go off briefly, but comes back on. The battery voltage drops from 14 to 12, then 10. There was one time the battery died completely. Need some help identifying where else this problem can come from.

My car has 150000 miles.
My car has an automatic transmission.

Confirm that there are no parasitic loads while the car is both idle and running. The grounding of the alternator should be checked. If grounded through the block, make sure all engine to body grounds are adequate. The actual output of the alternator should be measured at the battery terminals and if no obvious wiring issue exist, and there are no parasitic loads, you can record alternator output, on a data logger, to get some insight into what the cause is. There are other steps (from the Factory Service Manual) and to have the cause identified, please request an electrical diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Brakes or transmission causing my vehicle to not speed up. It feels like something is dragging.

Hi there. This sounds like the rear brakes on your vehicle are not adjusted right or the brakes are in need of service. The rear brakes on your vehicle are producing a brake drag after the brakes are applied, and...

Blown fs/asd fuse shuts down while driving

Hi there, thanks for writing in. Unfortunately, this is an issue that is still somewhat unresolved to the car community. I would recommend taking the car to the Dodge Chrysler dealer to interpret these codes, as these are not readily...

Clicking sound when turning over.

Hi There, It sounds like you may have a faulty starter solenoid or starter relay. If you hear a clicking sound when turning the key, it is likely that your starter solenoid may be faulty. The starter solenoid is located...

Related articles

The Best Used Cars to Buy If You're Towing a Boat
If If you’re towing a boat, the vehicle that you buy is largely going to depend on the size and weight of your boat plus trailer. Most cars, realistically, aren’t cut out for the job. We recommend a pickup truck...
A Buyer’s Guide to the 2012 Chevrolet Malibu Hybrid
The The 2012 Chevrolet Malibu ECO hybrid is an interesting car in the world of mid-size family sedans. Unlike other popular hybrids, it doesn’t have a full-sized electric motor that takes over when the car starts. Instead, it uses eAssist...
The Best Used Cars to Buy If You Have 3 or More Kids
If If you have three or more kids, you could probably get by with a mid-size sedan if all you want to do is take them from Point A to Point B. Realistically, though, having kids means music lessons, athletics,...