Symptom: Terminal beeps and auto-steer disengages without user intervention (override).
Cause: The GPS signal Std Dev (Error, or deviations of DGPS solutions in ft) exceeds the limit at which the filters can maintain auto-steering. Monitor the Std Dev. in the MAX, STX, or REBEL’s GPS Details page. If auto-steering is engaged and the Std. Dev. exceeds normal limits, the system generates an audible alarm (the beep) and disengages auto-steering.
Resolution: The normal condition for WAAS or SBAS is a Std Dev. of .1 to .75 depending on atmospheric and satellite signal conditions. The most likely cause of erratic deviations in the Std Dev. is a faulty internal GPS board, which will need to be replaced: contact Customer Support.