Volvo All Engines (2004 Emissions) Fault Code: PID 105 FMI 4 Boost Air Pressure / Temperature Sensor

Fault Condition: The Electronic Malfunction Lamp (EML) will turn on and PID 105 will set when the EMS Module senses that the Boost Pressure and Temperature Sensor signal voltage is less than 0.1 volts or greater than 4.55 volts. If the Boost Air Pressure/Temperature Sensor voltage is between 0.1 volts and 4.55 volts, the fault will become inactive.

Possible repairs:

Turn the ignition key OFF first.

1) Disconnect the Boost Air Pressure/Temperature Sensor connector. Measure the resistance between pins 1 and 2 of the Boost Air Pressure/Temperature Sensor with the ambient air temperature between 32° and 203°F (0° and 95°C). If the measured resistance is NOT between 5887 and 213.67 ohms, replace the sensor.
2) Disconnect the Boost Air Pressure/Temperature Sensor connector. Check for continuity between pin 1 of the Boost Air Pressure/Temperature Sensor and a good ground. Check for continuity between pin 2 of the Boost Air Pressure/Temperature Sensor and a good ground. Check for continuity between pin 3 of the Boost Air Pressure/Temperature Sensor and a good ground. Check for continuity between pin 4 of the Boost Air Pressure/Temperature Sensor and a good ground. If continuity exists on any pin, replace the Boost Air Pressure/Temperature Sensor.
3) Disconnect the Boost Air Pressure/Temperature Sensor harness connector. Measure the resistance between pins 1 and 2 of the Boost Air Pressure/Temperature Sensor with the ambient air temperature between 32° and 203°F (0° and 95°C). If the measured resistance is NOT between 5887 and 213.67 ohms, replace the Boost Air Pressure/Temperature Sensor.
4) disconnect the Boost Air Pressure/Temperature Sensor harness connector. Disconnect Engine Management System (EMS) Module connector A. Check for continuity between pin 2 of the Boost Air Pressure/Temperature Sensor harness connector and Engine Management System (EMS) Module harness connector A pin 47. If there is NO continuity, locate and repair the open in the signal circuit between the Boost Air Pressure/Temperature Sensor harness connector and Engine Management System (EMS) Module harness connector.
5) Disconnect the Boost Air Pressure/Temperature Sensor harness connector. Connect connector A to the Engine Management System (EMS) Module. Turn the ignition key ON. Measure the voltage between pin 2 of the
Boost Air Pressure/Temperature Sensor harness connector and a good ground. If the measured voltage is between 4.8 and 5.15 volts, check the Boost Air Pressure/Temperature Sensor harness connector for deformed pins or insufficient contact with the Boost Air Pressure/Temperature Sensor pins. If the pins are not damaged, replace the Boost Air Pressure/Temperature Sensor and retest the system. If PID 105 is still active, replace the EMS Module and retest the system.
6) Connect the Boost Air Pressure/Temperature Sensor harness connector. Connect connector A to the Engine Management System (EMS) Module. Turn the ignition key ON. If PID 105 is still active, check the Engine Management System (EMS) Module and connectors A, and B for dirt, loose or shorted pins, or any other repairable damage. If no problems are evident, or are NOT repairable, replace the Boost Air Pressure/Temperature Sensor and retest the system. If PID 105 is still active, replace the EMS Module and retest the system. If PID 105 is NOT active, the diagnostic procedures have corrected the problem. Check all connectors to ensure proper connections.