battery light when secondaries open...

[tauruswithheart]

does anyone have a clue why my battery light would come on when the secondaries open then turn off?

 

[Phoenix]

You will need a new alternator , or a rebuild.

Don't wait up

 

[93rev2sev]

First step is to try a new belt. It could be slipping when the secondaries open.

 

[tauruswithheart]

it only happens in the rain.....so it might be the belt....the alternator was replaced at 129k at the dealership....it now has 173k....ive never had chargin issues and im running an optima red top which are notorious for dead cells but its reading 12.97 volts....soo

 

[Phoenix]

Well the slipping belt could be it too , make sure it's tight and the belt is good.

The optimum reading for a running vehicule is 14.4 V @ idle. and 12V @ Not running.

And a Batt light will never come up for a dead/defect battery.

 

[projectSHO89]

12.97 for a running engine means your alternator is toast....

Since you have floating brushes, it's definitely time for rebuild or replacement.

Steve

 

[tauruswithheart]

engine was off....tested alternator with snapon tester says diods good alternator good.....max out put 127 amp...the fluke measured 12.97 at the battery shortly after i was done driving for a while.....while running btw the battery was around 14.1 it fluctuates around there..14.14 14.2 14.07