2010 Hummer H3 Owner's Manual - Page 148

6-4 Lighting Vehicles first sold in Canada cannot turn off DRL unless certain conditions are met. See Exterior Lamp Controls on page 6‑1. The system can turn on the headlamps when driving in a parking garage, through a tunnel or when there is overcast weather. This is normal. There is a delay in the transition between the daytime and nighttime operation of the Daytime Running Lamps (DRL) and the automatic headlamp system so that driving under bridges or bright overhead street lights does not affect the system. The DRL and automatic headlamp system will only be affected when the light sensor detects a change in lighting lasting longer than the delay. If the vehicle is started in a dark garage, the automatic headlamp system comes on immediately. Once the vehicle leaves the garage, it takes about one minute for the automatic headlamp system to change to DRL if it is light outside. The DRL system comes on when the following conditions are met: . . The ignition is on. The exterior lamps control is in AUTO. The transmission is not in P (Park), if the vehicle has an automatic transmission. The light sensor determines it is daytime. . Automatic Headlamp System When it is dark enough outside, the automatic headlamp system turns on after the transmission has been shifted from P (Park) to D (Drive). The headlamps, taillamps, sidemarker, parking lamps, roof marker lamps, and the instrument panel lights turn on at normal brightness. The radio lights will become dimmer when the headlights are off compared to when the headlights are on. The vehicle has a light sensor located on the top of the instrument panel. Do not cover the sensor, or the system will be on whenever the ignition is on. . When the DRL are on, no other lamps are on. The instrument panel will not be lit up either. For vehicles first sold in Canada, if parking lamps are manually turned on, DRL will stay on. When it begins to get dark, the automatic headlamp system changes from DRL to the headlamps. The regular headlamp system should be turned on when needed. To turn off the DRL, see Exterior Lamp Controls on page 6‑1.