Nav Pilot 700; No Nav Data Wait for 1 seconds

[pmai]

I have a TZT2BB, new last year and the original Nav Pilot 700 (2015) that have been working fine until this past week. When i try to Nav to a point it alarms and says "No Nav Data". Also, heading hold is operating erratically.

 

[Sparky Wire]

That sounds like two different issues. Holding a heading (called AUTO mode) only requires HEADING and hydraulics to be working properly. I would first check your heading reads roughly the same as your COG and Steering compass when moving straight (all four directions). If the heading is wrong, that needs to be fixed before anything can move forward in AUTO or Nav mode. If heading is good all four directions, then it sounds like something is up with the hydraulics. Checking hard over times, rudder test should help you narrow down what is happening. What is the hard over to hard over when using the pump (dodge buttons) and what does the Rudder test say (when ran in the water with engines at idle).

 

[pmai]

ok, steering fluid is down a bit (1/4 of the glass bulb) , and i found some fluid in the bilge. while i'm hunting down the source of the leak, could this be the cause of all my issues?

 

[Johnny Electron]

Air in the hydraulics can definitely be an issue as well as leaks.

 

[Sparky Wire]

Agreed. Low fluid/air or leaks is not good for an autopilot to hold the rudder/engines.

 

[jp498]

Air in the system can cause bubbles/frothing in the lower pressure hydraulic fluid storage tank causing it to overflow/vent. This would cause a mess and loss of some fluid by not a lot at once.

 

[pmai]

does anyone know if the Navpilot 700 has its own hydraulic pump for steering or does it communicate with the SeaStar pump for steering?

 

[Johnny Electron]

The pilot doesn't sell with a pump. It is custom fit to the boat/install. Some boat steering systems have a dedicated pilot connection so only the installer would know what they did when they installed it. You of course can look at what the pilot is connected up to on the boat and see what they did.

 

[pmai]

ok, yes that aligns with what we are seeing. the hunt continues!

 

[pmai]

So here we are again a year later. All of a sudden I get No NAV Data alarm again but the Auto mode works. I'm going to try this: I would first check your heading reads roughly the same as your COG and Steering compass when moving straight (all four directions). If the heading is wrong, that needs to be fixed before anything can move forward in AUTO or Nav mode.

I assume I'm going to find there are discrepancies but why does this keep happening? How do I correct the situation?

 

[Sparky Wire]

You might need to get a dealer on the boat if you can't work thru it. Troubleshooting isn't everyone's cup of tea. There are so many ways for steering systems, electronics and pumps to have problems. There is no magic wand, the problem needs progressive troubleshooting.

 

[pmai]

sure I will but that will take weeks, in the meantime...the pilot needs to be looking at the chartplotter for the nav data. I know how to get into the program level of the pilot, what should the settings be to properly receive the Nav data?

 

[Johnny Electron]

Pilot NavData (Steering Instructions) normally comes from the chart plotter with an active GOTO or active route. The installer should ensure the needed PGNs (if 2000 interfaced) or 0183 Sentences are turned on. In the pilot the pilot sources should be setup correctly to read those provided sentences. Pilot only needs speed and heading to conduct AUTO mode but needs NavData sentences if driving a GOTO or route.

 

[pmai]

Great, I'll start with this, thank you!