2006 Pontiac GTO Owner's Manual - Page 124

Charging System Light The charging system light will come on when you turn on the ignition, until the engine is started, as a check to show you it is working. One-to-Four Shift Light (Manual Transmission) When this light comes on, you can only shift from FIRST (1) to FOURTH (4) instead of FIRST (1) to SECOND (2). When the engine is running, the light should go out. If the light illuminates and the Check Alternator message on the trip computer stays on, or comes on while you are driving you may have a problem with the electrical charging system. It could indicate that you have a loose generator drive belt or another electrical problem. Have it checked right away. Driving while this light is on could drain your battery. If you must drive a short distance with the light on, be certain to turn off all your accessories, such as the radio and air conditioner. The Check Alternator message will remain until the MODE button on the trip computer is pressed, but the symbol will remain until the problem is fixed. See Trip Computer on page 3-33 for more information. You must complete the shift into FOURTH (4) to turn off this feature. This helps you get the best possible fuel economy. After shifting to FOURTH (4), you may downshift to a lower gear if you prefer. 3-26