Battery not charging

2002 GMC ENVOY
158,000 MILES • 4.2L • 6 CYL • 4WD • AUTOMATIC
Avatar
HAUCKELEGH
  • MEMBER
  • 2 POSTS
The Battery light is on. The car slowly shut off while I was driving home.
Mar 14, 2018 at 5:05 AM
Advertisement
Avatar
ASEMASTER6371
  • ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
Good morning.

Make sure the belt is turning the alternator.

The next step is to check the voltage at the back of the alternator. The most common failure is the alternator itself.

Do you have a voltmeter to do some checks?

Roy
Mar 14, 2018 at 5:09 AM
Avatar
HAUCKELEGH
  • MEMBER
  • 2 POSTS
The belt will turn but it is very hard to make it move. Afraid I do not have a volt meter.
Mar 14, 2018 at 5:31 AM
Avatar
ASEMASTER6371
  • ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
Okay, can you get one? We need to check the voltage at the back of the alternator to verify its failure. you can rent one at a parts store.

Roy
Mar 14, 2018 at 5:34 AM
Avatar
PATENTED_REPAIR_PRO
  • ASE Certified Mechanic
  • 1,853 POSTS
  • ASE Certified Mechanic
Very hard to make what move?
Mar 14, 2018 at 7:44 AM
Avatar
HAUCKELEGH
  • MEMBER
  • 2 POSTS
The belt will turn but it is very hard to make it move.
Mar 14, 2018 at 12:02 PM
Avatar
PATENTED_REPAIR_PRO
  • ASE Certified Mechanic
  • 1,853 POSTS
  • ASE Certified Mechanic
Are you trying to move the belt by hand?
If you have the key on run, the alternator will be live and difficult if not impossible to turn.
I think what asemaster meant was just to look at the belt while the engine was running and make sure the alternator is spinning.
Mar 14, 2018 at 3:17 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.