I posted here a couple of weeks ago about a high pitched humm i heard from the car.
I was suggsted it could be a pulley. WIth the hood popped though, i cant hear a thing.
Just today i was playing around with my headlights, and noticed that when my blinkers are flicking, the noise comes and goes with the drawing of power. So i then turned my headlights off and back on. The noise goes away for less than a second, and comes back once the headlights are fully lit.
What can cause this type of noise throughout the electrical system? could my alternator be going? i also epierience dimming of lights at some times. Is it possibe for an alternator to work fine but be noisy? Thanks!
To test the Alt, Just use a digital meter, It will show you if youre battery is @ 12.5 Volts, Also it will show you with the car runnig if the Alt is charging 13-14.6 volts. If no charging youre Alt is burning out.
Good Luck.
Yup, if diodes or rectifier is starting to go bad, or bearings in the alt, all those symptoms will show.
Your car may do 13 sec @ 103 mph, but my car does 146db @ 35 hz.
Where can i test the alt voltage while the car is running? i cant seem to find posts.
You take red lead of the digital multimeter, connect it to the positive terminal of the alterntaor, the black end of the multimeter goes to the battery ground, if it is below 14V at idle, your alternator is not charging correctly
- 2004 Cavalier - 124k, owned since new
Yes lol
But i cant find the terminals of the alternator. What side are they on? i see a red wire but it seems to be part of a plug of some sort?
Just check it at the battery..The red wire on the Alt is going down to the starter then right to the battery
My apologies.
im not so familiar with charging systems.
Its reading within the "healthy" voltage zone.
So where is my light dimming coming from?
What are you talking about, this healthy voltage zone.
You need to measure actual charging voltage, that red plug, the little plastic connector, it pops off, connect red lead to it, connect black to battery negative, start vehicle,what is the voltage reading on the multimeter?
- 2004 Cavalier - 124k, owned since new
Take a long 3/8 extension and while car is running hold it on the alternator (carefully) and take hand and hold it next to your ear on your head in front of your ear. If the bearings are wearing you'll hear it making a grinding sound and it will get louder under a load like headlights on high beam, turn signals operating ect.
Even if the voltage is okay it could be time to change it. If its quiet enough ( do same test with another car to compare). Maybe the battery is getting a bad cell in it, and won't hold a sufficent charge.
