If service brakes fail to operate while the vehicle is in motion, you can make an emergency stop with the parking brake. The stopping distance, however, will be much greater than normal.
WARNING - Parking brake
Applying the parking brake while the vehicle is moving at normal speeds can cause a sudden loss of control of the vehicle. If you must use the parking brake to stop the vehicle, use great caution in applying the brake.
Repair procedures
Refrigerant Recovery
Use only U.L.-listed service equipment that is certified to
meet the requirements of SAE J2210 when removing HFC-134a (R-134a) from
the air conditioning system.
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3. Exhaust emission control system
The Exhaust Emission Control System is a highly effective system which controls
exhaust emissions while maintaining good vehicle performance. ...