I purchased a 2007 Dodge nitro with 76000 miles on it 3.7 l alternator is working but when I hook computer to it it says slow charging it's not putting out enough to charge the battery why is that
No lights are on when I hook the computer to it it says slow chargeThe most common reason for an alternator failing to charge a battery is one of them going bad. You can easily test the voltage by connecting a voltmeter to your battery while the engine is off. The voltage reading should be between 12 and 13 volts. You can automatically assume there’s a battery problem when the reading is lower.
In the event your battery’s good, start the vehicle and get the engine up to 2,000 RPM. This will put a lot more demand on the alternator. A decreasing voltage reading on your voltmeter indicates you have an alternator problem.
I posted another Article in the Dodge Nitro :Battery issues? (at the end #29) Bad Voltage Regulator Symptoms and I still think it must be the voltage regulator . Some automotive parts (Auto Zone) stores do a free battery/ alternator check. Free is good and that might help solve your issue.
Do you have any error codes or "dash check engine light" ?