See also:

Emissions Inspection and Maintenance Programs
Some local governments may have programs to inspect the on-vehicle emission control equipment. For the inspection, the emission system test equipment is connected to the vehicle’s Data Link Connecto ...

Engine Fan
If the vehicle has a clutched engine cooling fan, when the clutch is engaged, the fan spins faster to provide more air to cool the engine. In most everyday driving conditions, the fan is spinning slo ...

When the System Does Not Seem To Work Properly
If the LDW symbol does not appear: ○ The lane markings on the road may not be seen. ○ The camera sensor may be blocked by dirt, snow or ice. ○ The windshield may be damaged. ` ...