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.

Electric Problems Inspection $79.99 - $89.99 Get a Quote

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.

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

What others are asking

How do I close the power liftgate?

If your vehicle is in power liftgate mode, you can use the power liftgate close button to effortlessly close the trunk. To do so, press the liftgate close button, which is located directly next to the latch on the trunk....

My vehicle occasionally heats up and blows cold air out of the heater vents.

If you are getting the heater to work sometimes and other times not then it is due to the engine cooling system has air in it. You should have the cooling system purged of air and then retest system. As...

ABS/VDC/Slip light on.

Hello. If these lights were not on prior to replacing these parts then you need to start by checking the brake fluid. Low brake fluid or a bad brake fluid level sensor will cause this problem. If the fluid and...

My 04 Nissan Altima sometimes when putting in drive will roll backwards instead of moving forward when I give it gas .. sometimes

What you are describing may be a result of a faulty speed sensor, potentially low transmission fluid or a even a faulty transmission control solenoid. As your vehicle travels down the road, the computer analyzes data being sent by vehicle...

Chevrolet Avalanche fuel pump replacement

Hi King. Thanks for writing in today. You can request an estimate to have one of our mobile mechanics complete the fuel pump replacement for your Chevrolet Avalanche by clicking this link to the service page](https://www.yourmechanic.com/services/fuel-pump-replacement). In regards to doing...

starts then cuts right off and security light flashes twice.

The most common causes for this are the ignition lock cylinder or the PassLock sensor for the Vehicle Anti-Theft System. The lock cylinder and/or key may need replacement as well. Try and have this done first. If it fails to...

Timing off in vehicle.

Greetings! Have a trained technician, like the ones here at YourMechanic, come out and take a look for you. The mechanic will be able to turn the engine over to determine why the car is not starting and confirm proper...

How do I use the sunroof?

The sunroof that is available as a option in the vehicle is different depending on the model of the truck; In the extended cab model, there is a single switch with a symbol representing the sunroof printed on it...

hey i had a belt break while traveling on my 2004 honda pilot. It is the small belt and not the serpentine belt. The mechanic t

Hello. The smaller belt is known as your timing belt, and it works inside the engine to keep mechanical components aligned with each other during the compression cycle. The serpentine belt, which is the big belt, drives the alternator, water...

Related articles

A Buyer’s Guide to the 2012 Chevrolet Camaro
The The 2012 Chevrolet Camaro is an exciting car that says a lot about American drivers and what we want. While fuel prices are high and the economy is just barely starting to resurge and stabilize after years of recession,...
A Buyer’s Guide to the 2012 Chevrolet Avalanche
Few Few vehicles are as distinctive as the Chevrolet Avalanche. Part SUV, part truck, the Avalanche is actually surprisingly practical. On the inside, it feels more like a Chevy Tahoe, except when you look out your rearview mirror, you’ll notice...
The Best Used Cars to Buy If You Have Limited Mobility
When When you have limited mobility there are a number of challenges you face, one of these can be with your vehicle. Finding a car that meets your specific needs, and addressing your challenges can mean the difference between being...