Raymarine C120 GPS Signal problem

[z1ppy]

Afternoon,

i know i will be lacking some information here to get full answers but some pointers would be great.

We have a Raymarine C120 on the boat which seems to struggle with GPS signal after switch on. it will not get a signal at all, if i go into the gps set up section of the menu and select restart gps it will find signal and be fine until its switched off and the process starts again.....

everything else works fine, AIS and Radar but seems to struggle with initial signal for some reason?

anyone experienced anything like this?

 

[stuartwineberg]

Do you have any other devices like the VHF taking the GPS feed from the same aerial - that would exclude/point to the aerial being the cause. There are many threads here about the batteries failing in the GPS mushroom and causing intermittent problems

 

[DavidJ]

There are many threads here about the batteries failing in the GPS mushroom and causing intermittent problems

+1
If your GPS Sensor unit is 8 years old or more it's the battery. The Raystar120 has the battery welded in so you need to grind it out with a dremmel and replace with a Varta CR2032 with solder tags.

If your GPS sensor (mushroom) is a Raystar 125 the batteries are replaceable I've been told.

Best of luck.
There are cheap replacement units on ebay which others will guide you towards I'm sure.

 

[SpottyDog5]

Copied from Ray marine site.


RS125 - NO FIX being reported on Pathfinder Series Display or Multifunction Display





NO FIX is being reported on Pathfinder Series Display or Multifunction Display . I have a Raystar 125 GPS Sensor supplying the display with GPS data. How can I diagnose and correct this problem?


Raymarine's Multifunction Displays have no inherent GPS capabilities. These displays rely on an external GPS data source to provide position, course over ground (COG), and speed over ground (COG) to the display. Raymarine's Raystar 125 GPS Sensor (RS125) was produced to satisfy the external GPS data source requirements of these displays. The RS125 GPS sensor can be wired for use as a SeaTalk or NMEA 0183 device.


Before beginning diagnostics, verify the following:
1) that the problem can be reproduced at the time of this diagnostic;
2) that the boat's batteries are fully charged or that you are connected to shore power;
3) if you have more than 5 SeaTalk devices, it is recommended that a second power insertion point be added after the last SeaTalk device to ensure adequate sufficient power to the SeaTalk network.





The following diagnostic can be used to troubleshoot a NO FIX condition for the RS125 installed as a SeaTalk device (most common). Verify the following:


verify that the GPS is installed such that it has a clear view of the horizon and is not installed below any hard surfacesverify that the GPS is not installed within 3' of a radar scanner (if mounted within its beam angle) or VHF antennacheck the status LED atop the RS125:Not illuminated: the device is not powered or suffered a total failureFlashing RED: the unit is booting up, its software is being upgraded, or is unable to bootFlashing ORANGE: the unit is running, but does not have a FIXFlashing GREEN: the unit is running and has a fixensure proper connections by unplugging RS125’s cable from the sensor’s shell and checking the following with an analog voltmeter (Note: the RS125's power/data cable is removed by rotating the GPS Sensor's power/data cable plug's locking ring in a counter clockwise direction. The pin numbers referenced in the below are assigned in a clockwise orientation from the plug's indexing groove (pin to right of indexing groove is pin 1)) :Between pin 1 and 2: +12VDCBetween pin 1 and 3: +12VDCBetween pin 5 and 2: +12VDCBetween pin 4 and 2: fluctuating +9 to +11VDC if connected to a powered SeaTalk device.Note: it is recommended that the RS125 be powered by the SeaTalk network (if so equipped) or a switched +12VDC source rather than from the Multifunction Display’s red SeaTalk lead.cycle power to the RS125 (verify that the power as measured between pins 1 and 2 drops to zero). This will force the GPS to reset. If the GPS acquires satellites and a FIX afterwards, the nothing more need be done.if pole mounted, ensure that the pole mount provided with the RS125 is not filled with water.

 

[Bathdave]

Interestingly there is a thread on pretty much the same subject running at the moment on the PBO forum, as I have been having similar challenges.

http://www.ybw.com/forums/showthread.php?422681-Raymarine-GPS-Reciver-batteries

 

[jimmy_the_builder]

Afternoon,

i know i will be lacking some information here to get full answers but some pointers would be great.

We have a Raymarine C120 on the boat which seems to struggle with GPS signal after switch on. it will not get a signal at all, if i go into the gps set up section of the menu and select restart gps it will find signal and be fine until its switched off and the process starts again.....

everything else works fine, AIS and Radar but seems to struggle with initial signal for some reason?

anyone experienced anything like this?

I had exactly this with a c120 classic. It was the GPS mushroom dying. It was easier to replace the mushroom than try and swap the battery. Once I'd fitted the new mushroom, all was well.

 

[z1ppy]

Thanks everyone,

Yes, we have other devices taking feed (vhf) and it does look like its the mushroom,

Need to go down and see what model it is and find replacement of new battery.

Does anyone know if it's a re route cable job or if we can just swap out the mushroom itself?

 

[SpottyDog5]

The Raystar 125 has removable plug in cable

 

[oldgit]

Early units are hard wired into mushroom GPS aerial . If somebody has replaced it previously,you may well find a bit of chocolate block connector lurking under the roof lining somewhere, connecting the old wiring to any replacement unit.This works perfectly well.In my case just joined old wiring to new and coiled up surplus.

 

[omega2]

Ours threw in the towel. read this and decided to replace it, with a Evermore GPS Ebay.

Raystar 112LP Missing Battery - Cruisers & Sailing Forums

Then a mate had a go at replacing the battery, on he raystar unit, and fixed it, by this time however the new unit was fitted.

 

[oldgit]

Ours threw in the towel. read this and decided to replace it, with a Evermore GPS Ebay.

Raystar 112LP Missing Battery - Cruisers & Sailing Forums

Then a mate had a go at replacing the battery, on he raystar unit, and fixed it, by this time however the new unit was fitted.

That what we used,came with a handy guide for the "hard-of-understanding" in what wire did what in both old and new stuff.

 

[z1ppy]

ok, so this problem came up after the main batteries had been drained flat.

first trip out after the main batteries had been charged and this happens, all following trips it has behaved like it should have!

will keep a close eye but at the moment it seems to be working well again. i do now know i have a Raystar 120 so will look for a direct replacement in slower time