Campbell Scientific OBS-Mobile Software for Archer-OBS - Manual (Page 21)

Section 2. Troubleshooting
This section will help you isolate problems that can be easily fixed such as
cable-continuity, processor reset, and battery replacement from serious ones
such as sensor, computer and electronic malfunctions, and damaged
mechanical parts that will require our help. The problem symptoms are shown
with underlined, bold text.
FIGURE 2-1. Component locations
Unit does not communicate with the Archer.
There are several possible causes for this symptom.
1. The test/umbilical cable is damaged or improperly connected.
2. The OBS-3A is sleeping and will not wake up.
3. The batteries are dead.
2-1