Pressure sensors
If the ambient temperature has been below freezing, the error may be due to ice forming in the sensor. Ensure that the sensor has had time to thaw before further action. If the sensor is thawed, and the problem persists, compare values from the boost pressure sensor and ambient pressure sensor. A functional sensor should show a value that corresponds to the current ambient pressure (~ 1000hPa at sea level) while the engine is not running. If the boost pressure sensor (T122) is wrong, check the wiring, connectors and installation. If it still deviates replace the sensor and run the test again. If the ambient pressure sensor (the COO, E30) is wrong, change the COO (E30) To verify that the fault has been cleared, make sure the engine is warm, turn the ignition on, wait a few seconds. Errors will be inactive immediately
What you'll see
No driver-visible symptom recorded.
System reaction
When the ambient temperature has been below freezing, there is a possibility of ice forming in the sensor.
Diagnostic depth
The ambient pressure sensor signal (In COO, E30) and the boost pressure sensor signal (T122) do not correlate. The ambient pressure sensor shows a higher value than boost pressure sensor
Boost pressure sensor (T122) may be defective or the installation may be clogged. Connectors can be corroded or wiring may be defective Ambient pressure sensor (in COO, E30) may be defective