Ok, so I have a 2009 Saturn Outlook.
I have been have battery draining issues sense purchasing the car 6 months ago.
The alternator has been replaced 3-4 times in these 6 months by a mechanic who said that it was because the aftermarket alts he was using were to weak to power the car. So the last one he put in was a GM alt.
The battery was also replaced by the mechanic.
The problem still continues.
So what happens is, my car will start and the volts will stay between 13 and 14.5.
Then when I turn my fan motor on (ac button not on) there is a power serge, the lights dim and the volts drop down to about 11 and stay there. If I rev the engine they come back up, if I turn the fan off they they stay there for a min and then the engine revs it’s self up slightly and the volts go back up on their own. Then I turn the fan on again and it happens all over again. Could it be the wiring harness, fan motor, or maybe the blower motor resistor? I’ve never seen this kind of behavior in a car before. Please help.
Did the mechanic check the battery current sensor?
The computer uses this sensor to regulate the voltage out of the alternator.
Tester
No I don’t believe he did. He’s the dealerships mechanic, the dealership is no longer covering the repairs, so I am on my own. Where is it located and how do I test it?
The sensor is mounted on the battery tray.
You have to remove the negative battery cable from the vehicle in order to replace the sensor.
The part costs so little, I’d just replace it.
Tester
If you bought a 2009 used car from a dealership 6 months ago, and the dealership mechanic can’t figure out what’s wrong with it, you need to find a different mechanic and file a complaint here about the used-car dealership: https://www.usa.gov/car-complaints Obviously the mechanic has no idea what he is doing, and likely told the dealer the car was ready to sell. It sounds like you got ripped off, I am sorry.
The best way to find a good mechanic is word of mouth through friends, or customer reviews on Yelp or Google. You can get great advice here on CarTalk as well, but you need to file the request for help under the make/model of your car, which it doesn’t look like you did. Here is where you should go:
https://community.cartalk.com/tags/outlook
Good luck. (Not saying Tester’s advice isn’t good, but going directly to the make/model community will likely reap more responses.)
File a complaint about the dealership ? Where does it say they did anything wrong . The purchase was most likely an As Is deal . The problem is this mechanic does not sound like he knows what he is doing .
Maybe checking the current draw of the blower motor would reveal a problem. It’s amazing how much current a small DC motor can pull when it’s about to seize up.
And when current goes up voltage goes down and vice-versa.