BEARING 2H3841 - Caterpillar

Diagnostics
Measure the value of the resistance in the fresh air sensor. See "Specifications". Proceed to step 2.
If the resistance value is incorrect see step 3. If the resistance value is correct see step 4.
Replace the fresh air sensor.
Disconnect the connectors from the sensor and measure the voltage between the connectors OR/BU and GY/YL. See "Specifications". Proceed to step 5.
If the voltage value is incorrect see step 6. If the voltage value is correct see step 7.
Check the harness and repair the harness between the connector and the control panel. Also, check the system power source.
Fit the sensor and measure the voltage between terminals 10 and 14 of the control panel. See "Specifications". Proceed to step 8.
If the voltage values are incorrect see step 9. If the voltage values are correct see step 10.
Check the harness and repair the harness between the connector and the control panel.
Replace the control panel.Specifications
Resistance in the fresh air sensor 25 °C (77 °F) ... 1700 ΩVoltage between connectors ... 5.0 VVoltage between terminals 10 °C (50 °F) ... 2.00 V 20 °C (68 °F) ... 1.49 V 25 °C (77 °F) ... 1.25 V 30 °C (86. °F) ... 1.06 V