NorthStar Navigation 978/897-6600 Marine GPS System User Manual


 
SECTION SEVEN: Troubleshooting and servicing the 958 system
958 Installation Manual, Rev. A1 Page 37
TABLE 12: Troubleshooting the 2201 and 2301 installation
If . . . Then . . .
Satellite signals are often lost, or the 2201
works while youre travelling in one
direction, but not the opposite one.
The 2201 or 2301 may be partially shaded by metallic objects around
it. Re-position or raise the 2201 or 2301 away from the object for a
better satellite view.
Signals may be lost when the 2201 or 2301 is under a bridge or when
shielded by buildings.
Poor SNR readings are obtained even
after running the 958 for several minutes
Check the quality of the antenna locationthe antenna should have a
clear view of the sky. For the correct antenna placement, see Figure 8
on page 13.
Make sure the antenna is clean, and not covered with ice, snow, or
exhaust soot.
Youre having difficulty obtaining WAAS
satellites
Check that WAAS is available in your operating area.
Reset the 958s satellite elevation setting to its default (10 degrees).
Check that the 958s
DIFFERENTIAL OPERATIONS
option is set to
either
WAAS
or
AUTO.
The following error message appears on
the 958 display:
COMM FAIL
TOO FEW SATS
With power on, check the antenna and wiring connections.
Disconnect the 2201 or 2301 from the 958, then measure the 7-pin
2201/2301 connector for 10 - 36 volts at pin 7, ground at pin 6.
Check the 2201 or 2301s remote-on: Pin 5 should measure less than
5 ohms to ground.
After testing above, re-connect the cable and press the
PWR
key to
turn the 958 off, then turn it back on again.
Check if anything is blocking the 2201 or 2301s view of the sky.
The almanac may not be complete; allow up to 30 minutes for full
initial acquisition.