GMC Sierra Quiz
Instruments and Controls

Malfunction Indicator Lamp

In this manual: Instruments and Controls
Introduction — 6In Brief — 46Seats and Restraints — 48Storage — 7Instruments and Controls — 75Lighting — 22Infotainment System — 22Climate Controls — 7Driving and Operating — 77Vehicle Care — 79Service and Maintenance — 26Technical Data — 8Customer Information — 25OnStar — 25Keys, Doors, and Windows — 38
~1min read

A computer system called OBD II (On-Board Diagnostics-Second Generation) monitors the operation of the vehicle to ensure emissions are at acceptable levels, to produce a cleaner environment. This light comes on when the vehicle is placed in ON/RUN, as a check to show it is working. If it does not, have the vehicle serviced by your dealer. See Ignition Positions on page 9‑28 for more information.

GMS Sierra: Malfunction Indicator Lamp. If the malfunction indicator lamp comes on and stays on while the engine is running, this indicates that there is an OBD II problem and service is required.

Test yourself

A quick GMC Sierra quiz: every answer comes with an explanation and a link to the manual page.