This message is commonly caused by a defective membrane or dried electrolyte. This video tutorial will guide you through the steps to resolve the error message.

Possible CausesRecommended Actions
Membrane related (defective or dried up electrolyte) Change the membrane:
1) if it is damaged or missing, has a loose fit, or if there is trapped air or dry electrolyte under the membrane
2) if the ‘Sensitivity Test’ fails.
PCO2 electrode and/ or white PO2 sensing spot contaminated If after having changed the sensor membrane the ‘Sensitivity Test’ still fails contact qualified service personnel to clean the sensor without membrane.
SenTec TC Sensor defective If the problem persists the SenTec TC Sensor is defect. Replace it with a new one.
For more troubleshooting information, see our Service Manual.