VHF is displaying No GPS signal

The chart plotter often has its own built in GPS receiver or it can have an external aerial.
The chart plotter outputs a repeated signal (lat and long) on either a NMEA 2000 (if fairly new) or NMEA 0183. This is the protocol for output infiemation. (Very often both) This is then Plugged into the radio. Which one you have can possibly be determined by a mating plug (2000) or connecting up a few coloured wires (0183).
The manuals should make it a bit clearer.
Has it ever worked?
Sorry if this is teaching to suck eggs but is a simplistic start point without assuming prior knowledge
 
Have toy checked the pins in the connection plugs. Often easy to bend them connecting the plugs together, and then it wouldn't work. Be careful about bending them back they break easily.

Did the gps connection work before or is it a new set-up?
 
I don't know if it has ever worked (as I just bought the boat in December) but going by the fact that there is a cable connected to the GPS input I am assumming it did work at sometime.
the boat is wired using NMEA 0183
The Chart plotter is working and there are 2 GPS receivers on the pushpit.

As I am a complete novice at this, even very basic help is more welcome.
 
What is the radio, do you have a manual?
This could be a configuration issue whereby the chart plotter may need to be told to output lat and long and the radio need ps to be told to receive lat and long, both in NMEA 0183 format
 
From the manual:
2.6 NMEA Data
The Ray54E accepts NMEA 0183 (V1.5) data from a position determining
device (such as a GPS) to provide the Latitude and Longitude position
information that is transmitted during a DSC Distress Call.
When valid NMEA signal is detected, the GPS indicator appears on the LCD.
When no valid NMEA signal is detected, the NO GPS indicator appears.
Connect the NMEA OUT + and NMEA OUT – signals from the positioning
device to the NMEA IN + (yellow) and NMEA IN – (green) wires in the
radio’s NMEA cable.
 
Nothing else is plugged in

Hardly surprising that you have no GPS signal, then.

The manual shows a two-core cable with bare ends, for the NMEA0183 input, not a plug with an indeterminate number of pins.

I think you need to have a better go at describing what you have and what's connected to where.

Pete
 
raymarine.PNG
This is what the manual shows and what I am seeing

The power, Antenna & GPS are all plugged in. With as far as I am aware, no other device is connected to the GPS receiver.
So I assume that within the GPS plug there should amongst others be yellow & green wires.
would a meter testing something? be able to tell if a signal was being received?
Thanks again for your help.
 
Don't assume anything on behalf of previous owner installations!
You need to go past the multiway connector to where the wires join those of the GPS receiver. (ie the plug and socket both belong to the radio, not the GPS)
There should also be power to the GPS receiver. It will not get power from the VHF. If it's a Raymarine, the GPS may have an indicator LED.
 
If the boat has not been used for some time it might take a while to get a GPS position. Have you left it on long enough, say 15 mins?
 
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