Voltage variation

zstroken

zstroken

For $$$ your name here
This morning on the way to work I noticed my voltage really varying(noticed it about 5 miles from the house) as the headlights seem to be getting a little brighter/dimmer at a frequency of about 0.5-1HZ. My Brakesmart controller has a voltage gauge on it and it seemed to go from 13.4 ish to 14.4 ish. I assume it wasn't the grid heaters(being I am 5 miles from the house and it was around 50 degrees out) however maybe it was. At one point I flipped the high beams off, seemed to stop, flipped them back on started again, flipped them off, and it kept going. When I got to work, the truck was idling and it seemed to be rock solid. Revved it up to about 1500 RPM and still seemed rock solid.


Thoughts?
 
Last edited:
How is your alternator? On a camping trip this summer I noticed the same thing with voltage varying on my Edge display on my '04 almost exactly as you described. Before we came home it completely stopped charging and I had to replace it.
 
My alternator started doing almost that exactly, seemed worse on cool mornings. It finally went out completely about a yr later.
 
PSUCE said:
How is your alternator? On a camping trip this summer I noticed the same thing with voltage varying on my Edge display on my '04 almost exactly as you described. Before we came home it completely stopped charging and I had to replace it.
Click to expand...


Not sure, just noticed it this am, drove out for lunch and it seems hit or miss, seems like it will stabilize, but fire up the AC, or turn on the headlights and it starts back to doing it again. Truck is an 08 and only had 85K on it.
 
I’d test the grounds first and positive wire continuity, make sure some cable end isn’t corroded or a bad contact. Then the batteries with an actual load tester not one of these p.o.s. Algorithm dog sh!t units that shops have and coincidentally the things seem to almost always condemn the batteries... good for the shops bad for the consumer. Last I’d amp test the alt.
 
TheHammer said:
I’d test the grounds first and positive wire continuity, make sure some cable end isn’t corroded or a bad contact. Then the batteries with an actual load tester not one of these p.o.s. Algorithm dog sh!t units that shops have and coincidentally the things seem to almost always condemn the batteries... good for the shops bad for the consumer. Last I’d amp test the alt.
Click to expand...


Thanks, I really suspect it is the alternator or maybe a computer issue(I assume the computer controls the voltage regulation). It appears I can make it stop by decreasing the load(shut off AC/lights). Then make it start again by putting some load back on the alternator.
 
You must log in or register to reply here.
Back
Top