I have a 98 suzuki esteem with 7,8000 miles that developed a charging problem. I had it tested and found out the alternator output was low, but not low enough to light the warning lamp. At night in the rain everything quit under the heavy load but no warning light. The alternator was only charging at about 12.2 instead of the 14.5 it should be putting out. I replaced the alternator and when I started the car THEN the light on the dash came on : With the new alternator, the battery shows about 12.3 volts when the car is off, and when it is running the alternator is charging at 14.3v, but the light stays on. Do I just need to clear some codes somewhere? Can I do that without having to purchase a scanner or reader or whatever they are called? Why would I get no light when the system was malfunctioning, and then get a light AFTER the problem is corrected?