Weird electrical problem. need Help
Thread Starter
Instructor
Joined: Apr 2008
Posts: 163
Likes: 1
From: Long Grove Iowa
Weird electrical problem. need Help
Ok so I dont have power going too or from my alternater when the car is running or shut off.(test light doesnt light up on the alternator post.) Is there like a regulator that is blown? or what could be the problem?
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
You will get a lot more accurate help if you will remember to always include the year vette you are asking help for! All C4's are not made exactly alike.
There are three wires on the alternator plug and with the ign in run, all 3 should have 12v on them . Check the 10 amp gages fuse and the 3 amp cooling fan fuse with an ohmeter. The red wire goes to a fusible link and then to the battery and the alternator output wire also goes to a fusible link and to the battery. Both red wires should have 12v all the time and if not, the fusible link is suspect. If the output terminal has zero volts, then measure the resistance of the output terminal, if low resistance, then you have one or more shorted diodes inside the alternator.
There are three wires on the alternator plug and with the ign in run, all 3 should have 12v on them . Check the 10 amp gages fuse and the 3 amp cooling fan fuse with an ohmeter. The red wire goes to a fusible link and then to the battery and the alternator output wire also goes to a fusible link and to the battery. Both red wires should have 12v all the time and if not, the fusible link is suspect. If the output terminal has zero volts, then measure the resistance of the output terminal, if low resistance, then you have one or more shorted diodes inside the alternator.
