A computer system called OBD II (On-Board Diagnostics-Second Generation) monitors the operation of the vehicle to ensure emissions are at acceptable levels, helping to maintain a clean environment. The malfunction indicator lamp 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 9-13 for more information.
If the malfunction indicator lamp
comes on while the engine is running, this indicates that the OBD II system has
detected a problem and diagnosis and service might be required.
Malfunctions often are indicated by the system before any problem is apparent. Being aware of the light can prevent more serious damage to the vehicle. This system also assists the service technician in correctly diagnosing any malfunction.
Caution
If the vehicle is continually driven with this light on, the emission controls might not work as well,the vehicle fuel economy might not be as good, and the engine might not run as smoothly. This could lead to costly repairs that might not be covered by the vehicle warranty.
Caution
Modifications made to the engine, transmission, exhaust, intake, or fuel system of the vehicle or the replacement of the original tires with other than those of the same Tire Performance Criteria (TPC) can affect the vehicle's emission controls and can cause this light to come on.
Modifications to these systems could lead to costly repairs not covered by the vehicle warranty.
This could also result in a failure to pass a required Emission Inspection/Maintenance test. See Accessories and Modifications on page 10-3.
This light comes on during a malfunction in one of two ways: Light Flashing: A misfire condition has been detected. A misfire increases vehicle emissions and could damage the emission control system on the vehicle. Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
If the light continues to flash, find a safe place to stop and park the vehicle. Turn the vehicle off, wait at least 10 seconds, and restart the engine. If the light is still flashing, follow the previous steps and see your dealer for service as soon as possible.
Light On Steady: An emission control system malfunction has been detected on the vehicle.
Diagnosis and service might be required.
The following may correct an emission control system malfunction:
A few driving trips with the cap properly installed should turn the light off.
These conditions might go away once the engine is warmed up.
If one or more of these conditions occurs, change the fuel brand used.
It may require at least one full tank of the proper fuel to turn the light off.
See Fuel on page 9-35.
If none of the above have made the light turn off, your dealer can check the vehicle. The dealer has the proper test equipment and diagnostic tools to fix any mechanical or electrical problems that might have developed.
Emissions Inspection and Maintenance Programs
Depending on where you live, your vehicle may be required to participate in an emission control system inspection and maintenance program. For the inspection, the emission system test equipment will likely connect to the vehicle's Data Link Connector (DLC).
The DLC is under the instrument panel to the left of the steering wheel. See your dealer if assistance is needed.
The vehicle may not pass inspection if:
If this has been done and the vehicle still does not pass the inspection for lack of OBD II system readiness, your dealer can prepare the vehicle for inspection.
Service Publications Ordering Information
Service Manuals
Service Manuals have the diagnosis and repair information on the engines, transmission,
axle, suspension, brakes, electrical, steering, body, etc.
Service Bulletins
Service Bulletins give additional technical service information needed to knowledgeably
service General Motors c ...
Vehicle Load Limits
It is very important to know how much weight the vehicle can carry. This weight
is called the vehicle capacity weight and includes the weight of all occupants,
cargo, and all nonfactory-installed options.
Two labels on the vehicle show how much weight it may properly carry: the Tire
and Loadi ...
Turn and Lane-Change Signals
Move the lever all the way up or down to signal a turn.
An arrow on the instrument cluster flashes in the direction of the turn or lane
change.
Raise or lower the lever until the arrow starts to flash to signal a lane change.
Hold it there until the lane change is completed.
If the lever ...