After a new alternator my light is still on. says

I think I would check fuses and make sure you have good wire connections. If your battery ground is corroded or rusted badly you may have a bad connection and the battery will not charge properly. I found these link's which may apply to your situation.
Hope this will help

https://www.youtube.com/watch?v=FTGz0PKIl84

http://strongforsubaru.com/subaru-alternator-fault-fix/

Battery light is (more accurately) also named charging light or generator light.
One side of the light is connected to the battery via the ignition switch and the other is connected to the alternator. When the ignition is switched on, one side of the light is at battery voltage and the other side at 0 volts and so the light illuminates but when the engine starts and the alternator produces a full output both sides of the light is at the same voltage and so no current flows and the light is extinguished.

Assuming there are no wiring or connection problems your alternator isn't producing a charge. Perhaps you didn't need a new battery...

Running the car will drain the battery it if it's not charging ! An if your charging light is on it isn't charging ! Did you check power an grounds on the alternator ? There is a single heavier wire on the back of the alternator, this should have battery voltage ! You may want to take this to a ASE certified repair shop !
Functionality
With the ignition switch in the RUN position, voltage is applied through the warning indicator I circuit 904 (LG/RD) to the voltage regulator. This turns the regulator on, allowing current to flow from battery sense A circuit 35 (OG/LB) to the generator field coil. When the engine is started, the generator begins to generate alternating current (AC) which is internally converted to direct current (DC). This current is then supplied to the vehicle's electrical system through the output (B+) terminal of the generator.
Once the generator begins generating current, a voltage signal is taken from the generator stator and fed back to the regulator S circuit 4 (WH/BK). This voltage feedback signal (typically half the battery voltage) is used to turn off the warning indicator.
With the system functioning normally, the generator output current is determined by the voltage of the A circuit 35 (OG/LB). The A circuit 35 (OG/LB) voltage is compared to a set voltage internal to the regulator, and the regulator controls the generator field current to maintain the correct generator output.
The set voltage will vary with temperature and is typically higher in cold temperatures and lower in warm temperatures. This allows for better battery recharge in the winter and reduces the chance of overcharging in the summer.
Battery Positive Output (B+) Circuit 38 (BK/OG)
The generator output is supplied through the battery positive output (B+) terminal on the back of the generator to the battery and electrical system.
I Circuit 904 (LG/RD)
The I (ignition) circuit 904 (LG/RD) is used to turn on the voltage regulator. This circuit is powered up with the ignition switch in the RUN position. This circuit is also used to turn the charging system warning indicator on if there is a fault in the charging system operation.
A Circuit 35 (OG/LB)
The A (battery sense) circuit 35 (OG/LB) is used to sense battery voltage. This voltage is used by the regulator to determine generator output. This circuit is used to supply current to the generator field (rotor). The amount of current supplied to the rotor will determine generator output.
S Circuit 4 (WH/BK)
The S (stator) circuit 4 (WH/BK) is used to feed back a voltage signal from the generator to the regulator. This voltage is used by the regulator to turn off the charging system warning indicator. The S circuit is fed back externally on external mounted regulator generators.
Visual Inspection Chart Mechanical Electrical

• Battery case, posts, hold-down clamp, cables and connections
• Generator drive (serpentine) belt for condition and tension to make sure there is no slip between the belt and the pulley. For additional information, refer to Section 303-05 .
• Battery charge
• Generator pulley

• Battery junction box (BJB)Mega Fuse
• Battery junction box fuse:
  • 11 (20A)
• Central junction box (CJB) fuse:
  • 30 (30A)
• Circuitry
• Charging system warning indicator
• Cables

1. Check the operation of the charging system warning indicator lamp (instrument cluster). Normal operation is as follows:
   • With the ignition switch OFF, the charging system warning indicator should be OFF.
   • With the ignition switch in RUN and the engine off, the charging system warning indicator light should be on.
   • With the engine running, the charging system warning indicator light should be off.

1. Verify the battery condition. Refer to Section 414-01 .

Normal Charging System Voltages and Charging System Warning Indicator Operation Ignition Switch Position A Circuit 35 (OG/LB) S Circuit 4 (WH/BK) I Circuit 904 (LG/RD) Generator B+ Circuit 38 (BK/OG) Battery Engine to Battery Ground Charging System Warning Indicator Operation OFF 12 volts 0 volts 0 volts 12 volts 12 volts 0 volts Off RUN-engine off 12 volts 0 volts 1-3 volts 12 volts 12 volts 0 volts Illuminated RUN-engine running 13-
15 volts 1/2 battery voltage 13-
15 volts 13-
15 volts 13-
15 volts 0 volts Off

1. If the customer concern is verified after the initial inspection, refer to the Symptom Chart to determine which tests to carry out.
2. • The charging system warning indicator is on with the engine running (the system voltage does not increase)
   • Circuitry.
   • Voltage regulator.
   • Generator.
   • GO to Pinpoint Test B .
   Your whole problem is the alternator is not charging , a couple tests with a volt meter would tell you !

Is the battery light on the dash board working? If the light does not work the alternator will not charge, it needs the power from the light to energise the rotor.

CHECK WIRING THIS UNIT WILL CONTORT THE FIELD IN THE COMPUTER. THE FIELD CONTROL IS WHAT MAKES IT CHARGE.

On some of the earlier fords. If the bulb is blown in the instrument panel. It will not complete the circuit to charge. Turn your key on with the engine off to see if the red light comes on that shows the battery.

your alternator is probably buggered. check the voltage charge rate across the battery when the cars running expect 13.3 - 15 volts max. any less possibly replace alternator.

Since the voltage shows 0, that indicates the battery is not charging. You most likely need a new alternator. Drive the car (while you still can) to a parts store, they will check the charging system for free, and advise you on what to do to fix the problem.

It's possible the main fuse is blown. Have the battery fully charged and start the engine. With a digital volt meter, check to see if you have 12 volts going to your alternator (the large wire on your alternator) If not, the main fuse is most likely blown. The main fuse links your battery positive cable to the alternator 12 volt supply cable. It is probably mounted on your fuse box but probably won't be listed in your fuse box layout. Unbolt the battery and alt wires going to the fuse and check for continuity, ohms should be 0 or close to it. So now that you spent about $300 on a new battery and alternator, you find out it was a $5.00 fuse!

make sure you have power to the back of the alternator and make sure you have power from the plug