98 2.2 auto sedan with DRLs
I'm asking to help a friend. His cavalier has something wrong electricly. It seems like the is a short or bad wiring somewhere on it. Are there any common places to look at for stuff like this? The symtems are that nothing works sometimes. I tried the headlights and they didn't come one until I bonced the car a little then they worked normal. When I turned on the radio there was a pulsing sound. It would go away once the car was bounced then come back a few seconds later. The starter would crank but go down like the battery was dead. Measured 12.1 volts and then later the starter would do anything. I know I kind of rambled here but if I could get a starting point from you guys it would be appretiated. Thank you. John
from the sounds of it, it appears the voltage regulator inside your alternator is bad. the alternator produces a pulsating waveform (AC), it then passes thru the reulator cicrcuit, which basically converts it into DC waveform. if that circuit is bad, usually everything goes wacky....
an easy way to test, is with the car running (if it will), put a voltmeter on the battery. you should have a steady 13.8 - 15.2 volts. it may bounce .2 volts, but anything more is likely the regulator taking a poop. also, you can try just disconnecting the alternator, then run the car. obviously the battery needs a good charge, cause its gonna have to start, then run the car. if it stops your voltage is gonna drop, but it should not pulsate...
hope this helps.
If his electrical system is crappy with the engine off, I doubt the alternator is at fault.
2002 Cavalier 2200 5spd
Agree with Solid Snake
seems more like a bad connection on either of the battery terminals or the Negative ground point on the chassis/block.
Bouncing!! the car is probably moving the connection
Alont
Edited 1 time(s). Last edited Sunday, March 04, 2007 4:40 AM
I forgot to check the grounds so that is something easy to check. Are there any common places for wire damage to happen?
I agree with Alont.
The negative ground point at the block is a popular place for problems as I have noticed in this forum over the years.
Under the battery tray on some models/years
Alont
Thanks. Having some short of direction should help with when I go over Saturday to mess with it.