Automotive Terms And Abbreviations- O

O2- Oxygen
 
O2S- Oxygen Sensor
 
OBD- On-Board Diagnostics
 
OBD II- On-Board Diagnostics Second Generation
 
OC- Oxidation Converter Catalytic
 
OD- Outside Diameter
 
ODM- Output Drive Module
 
ODO- Odometer
 
OE- Original Equipment
 
OEM- Original Equipment Manufacturer
 
OHC- Overhead Camshaft
 
ohms- Ohm
 
OL- Open Loop, Out of Limits
 
ORC- Oxidation Reduction Converter Catalytic
 
ORN- Orange
 
ORVR- On-Board Refueling Vapor Recovery
 
OSS- Output Shaft Speed
 
oz- Ounce(s)