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

asked by on

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
  1. Home
  2. Questions
  3. 04 Avalanche "Battery Not Charging" even after new battery, alternator, ecm, and clean cables.

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

Q: fan somehow putting hole in radiator

Hi there. If all the mountings are secure, the only thing I can think of is something that is pushing the fan into the radiator. Have the engine and transmission mounts checked. If the engine and transmission are moving around...

Q: Oil pressure goes to 0 after 1 minute from start up

The engine specifications are 6 psi below 1000 rpms. It will go up 18 psi at 2000 rpm and 24 psi at 4000 rpm. The instrument panel will illuminate the Low Oil Pressure Light if the pressure is low from...

Q: 04 impala overheat changed waterpump n thermostat still overheat now stop running

At 200 thousand miles, the overheating could really be just about anything. But if you drove the car while it was overheating, there may have been some damage done that is causing your starting problem. Common causes of overheating are...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...