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If the Off Indicator Is Lit for an Adult-Size Occupant
If a person of adult-size is sitting in the front outboard passenger seat, but the off indicator is lit, it could be because that person is not sitting properly in the seat. Use the following steps ...

Interior
Manual inside rearview mirrors can be adjusted by holding in the center to move the mirror for a clearer view of behind the vehicle. Adjust the mirror to avoid glare from the headlamps behind you. ...

Vehicle Overview
The GMC Sierra 1500 and Chevrolet Silverado share the same platform, but the GMC product is often positioned as a more upscale offering. Mechanically, the trucks are the same. There might be sligh ...