» » »

Toyota Q&A

Ask Your Question

1990 Toyota 4Runner Question: why does the alternator light stay on after cranking

 

Question

unclehenry, 2.4L 4 Cylinder, Folsom, LA, December 05, 2011, 13:35
 Rookie

i installed a new alternator and it still stays on

3 Answers
Flag This
  • Answer #1

    euromech December 05, 2011, 13:56
     Journeyman

    Have you checked the voltage at battery positive and negative terminals while engine running.
    Reading should be between 13.2-14.4 voltage. Either lower or higher reading indicates bad battery; bad connection(to ground)
    or shorting in wiring.

    Reply
    Flag This
  • Answer #2

    PARTS GUY December 05, 2011, 18:04
    Profile_thumbnail
     Master

    The required voltage at the batery is a minimum of 13.5 volts and a maxium of 14.5. At idle with lights, A/C and wipers on it has to mantain 13.5 volts. You need to have the battery check and clean your terminals good.

    Reply
    Flag This
  • Answer #3

    patrick mannion from Greg Solow's Engine Room, December 05, 2011, 20:12
    Profile_thumbnail
     Master

    Just to add if the alternator is not charging on that cat the brake light and battery light will stay on (even if the brake fluid level is OK and hand brake is off.)

    Reply
    Flag This