A5/A3™ Service Manual 046-001141-00 2 - 35
Installation Guide Functional Tests
FIGURE 2-51 100% O2 Sensor Calibration Successful
2.3.3.3 Troubleshooting: O2 Sensor Calibration 
Failure Description Possible Cause Recommended Action
After [Start] is selected, 
calibration failure is 
prompted very soon. 
If the alarm [O2 Sensor Unconnected] is 
displayed, it indicates that O2 sensor is 
not connected.
Connect the O2 sensor.
O2 supply pressure is insufficient (lower 
than 200 kPa).
Change or connect the gas supply 
and make sure that O2 supply 
pressure is sufficient.
21% O2 calibration is not completed 
before 100% O2 calibration.
Perform 21% O2 calibration 
followed by 100% O2 calibration.
Calibration failure is 
prompted about 3 
minutes after 
calibration is started.
The O2% sampling value is not within the 
normal range. Namely, the sampling value 
of 21% O2 concentration is outside the 
range of 150~500 and the sampling value 
of 100% O2 concentration is outside the 
range of 800~2028. Access Setup →
Service → Data Monitors → VCV to check 
the O2% sampling value.
Replace the O2 sensor.
Error Code Description Recommended Action
00 00 00 02
O2 supply pressure is low. 
During 100% calibration 
process, O2 supply pressure 
was not sufficient.
. Check that the O2 sensor is connected to the cable 
correctly.
. Check the O2 supply pressure.
. Check that the O2 sensor output voltage in the calibration 
menu is steady.
. Replace the O2 sensor.
00 00 00 04
O2 sensor is disconnected. 
Sampled data is greater than 
2900 (AD value).
. Check that the O2 sensor is connected to the cable 
correctly.
. Check that the O2 sensor output voltage in the calibration 
menu is steady.
. Replace the O2 sensor.