Symptoms of Alternator Problems on a Lexus SC 400

• Alternator problems are sometimes difficult to diagnose. Alternator failure can exhibit mild to severe symptoms that can be initially overlooked. If you suspect that your Lexus SC 400's alternator is experiencing problems or has failed, look for telltale signs of trouble. Alternators perform the same function in every type of car.

Dead Battery

• If your Lexus's alternator is failing, your car may have a dead battery. Your alternator's job is to charge the battery. If you have a bad alternator, your battery will continue to die, even if you replace it with a new one. The only way to stop this problem is to replace the alternator.

Dim Lights

• A dying alternator causes your headlights to be dimmer than normal. They will continue to dim and fade until the battery completely runs out of juice and stops powering the car altogether.

Loss of Accessories

• If your alternator is failing, you may notice a loss of power to your vehicle's accessories as you travel. Items like your GPS, radio and even your dashboard lights drain power from the battery. If you turn your accessories off and your car seems to have a little more juice, or the dashboard lights get brighter, the problem is most likely your alternator.