VALVE-INLET 9L7682 - Caterpillar

System Operation Description:Periodic calibration of the oxygen sensor is required in order to ensure accurate readings and optimum engine performance. Refer to the Operation And Maintenance Manual for the maintenance interval schedule. The engine must be stopped and the sensor must be removed. The sensor must be placed in uncontaminated air in order to calibrate the sensor. The air must be free of exhaust.During the calibration, the Electronic Control Module (ECM) first establishes the reference for zero percent of oxygen by reading the sensor after the sensor has cooled for two minutes. The ECM energizes the heater in the sensor for five minutes. Last, the ECM reads the percent of oxygen in the surrounding air. The surrounding air is assumed to be clean with approximately 20.95 percent oxygen. The calibration offset and the calibration range are determined from these two points.Test Step 1. Inspect the Electrical Connectors and the Wiring
During operation, the oxygen sensor may reach temperatures that exceed 700 °C (1292 °F). Severe personal injury and property damage will result from contact with a hot oxygen sensor.Do not touch the sensor during engine operation, calibration, or testing. Allow the sensor to cool before moving the sensor. Wear gloves that resist heat. Do not place the sensor on or near any flammable material or any surface that can be damaged by high temperatures.
Set the engine control to the OFF/RESET mode. Remove the electrical power from the engine.
Thoroughly inspect the following connectors:
Connectors for the ECM
Connectors for the oxygen sensor and the oxygen buffer
Check the harness and wiring for abrasion and pinch points from the oxygen sensor to the ECM.Expected Result:All of the connectors, pins, and sockets are connected properly. The connectors and the wiring are free of corrosion, abrasion, and pinch points.Results:
OK - The components are in good condition with proper connections. Proceed to Test Step 2.
Not OK - At least one of the connectors, pins, or sockets are not connected properly. At least one of the connectors or the wiring has corrosion, abrasion, and/or pinch points.Repair: Perform the necessary repairs and/or replace parts, if necessary.STOPTest Step 2. Check the Atmospheric Conditions
Determine the ambient temperature, relative humidity, and barometric pressure.
Use Table 1 to determine whether your relative humidity is within the permissible range for calibration of the oxygen sensor.
Find the row for your ambient temperature.If the temperature is less than 12 °C (54 °F), use the 12 °C (54 °F) row.If the temperature is more than 38 °C (100 °F), do not calibrate the sensor.
Find the column for your barometric pressure.
Find the relative humidity in the cell that intersects your column and your row.If your relative humidity is equal to the humidity or greater than the humidity that is listed in the Table, do not calibrate the sensor.If the humidity is 90 percent or more, do not calibrate the sensor.
Table 1
Ambient Temperature, Barometric Pressure, and Relative Humidity for Calibration of the Oxygen Sensor    
Ambient Temperature     Barometric Pressure    
96 kPa (13.9 psi)
97 kPa (14.7 psi)