1999 Chevrolet Astro Owner's Manual - Page 138

yellowblue Service AWD Light (If Equipped) This light should come on briefly when you turn on the ignition, as a check to show you it is working. Daytime Running Lamps Indicator Light You will have this light on the instrument panel. It goes on whenever the Daytime Running Lamps (DRL) are on. The SERVICE AWD light comes on to indicate that there may be a problem with the drive system and service is required. Malfunctions can be indicated by the system before any problem is apparent, which may prevent serious damage to the vehicle. This system is also designed to assist your service technician in correctly diagnosing a malfunction. When it begins to get dark, the DRL indicator light is a reminder to turn on your headlamps. Check Gages Light This light will come on briefly when you are starting the engine. If the light comes on and stays on while you are driving, check your various gages to see if they are in the warning zones. 2-68