Navpilot 711c randomly shuts down after winter

AKfisher

New member
Im having Intermittent power issues with my nav pilot 711C with 2 head units that (until recently) have worked mostly fine since installed a few years ago. System randomly shuts down since i plugged in the 2nd head unit this month (after it was stored inside for winter -2nd head is at an outside station). Sometimes system beeps and starts to boot up then shuts down before diagnostic screen. Sometimes boots up and fine for a while but shuts down later, randomly. Problem seems to disappear (so far) when only the 1 inside head unit at main helm is connected.

The outside head is kept inside all winter..and outside data/Power plug is smeared with dielectric grease and sealed in a bag. I noticed this problem once or twice towards end of last fall, which was the first season after I had first greased outside connections for winter.

All connections look new, terminators plugged in both head units empty plugs. 2nd unit direct connect to system... not daisy chain. When working, voltage to unit shows 14.1. Unit is run through a new 20 amp breaker which has not tripped. Engaging the Autopilot does not trigger issue. Just random.

Maybe dielectric grease from winterizing outside connector/unit causing the issue? Maybe too much in sockets/on pins causing just enough resistance to cause issues? Lots of contradictory info out there on dielectric grease and resistance. I thought was ok oj tight connectors but maybe not? Should I clean out terminals with alcohol or crc cleaner? Or maybe totally unrelated to issue?

Any advice welcome!
 
Being you are running two heads (one to channel A and one to channel B) did you change the required jumper within the processor? (JP1 to pins 3-4)
Overall dielectric grease is a bad idea in my opinion. Almost anyone I have seen use it on data connections ends up having problems. For lights or power connections maybe it is good but data lines can be an issue depending on the compound. I just don't ever recommend it when talking to customers.
 
AKfisher":2fhngsdb said:
... Or maybe totally unrelated to issue?

Any advice welcome!

You could try troubleshooting the terminator, ohming pins 3 & 4 and verifying that it's a 120 ohm resistor. I'd just swap them out and see if that resolves it, Part no. 000-167-746 there should be a couple in stock.

Hope this helps, :sail

- Maggy
 

Attachments

  • 711terminator.jpg
    711terminator.jpg
    7.5 KB · Views: 213
Not sure about jumpers as processor professionally installed but I will open and check. Any recommendations on how to safely clean off dialectric grease from connectors?

I will test terminators as well thanks for replies!
 
A camel hair brush and some electrical contact cleaner should help get most of it off. Just make sure it is fully dry before putting back on for operation. While checking the terminator, also make sure there is no contact between pins 4 and 5 on the terminator. There was a bad batch about 6 months ago that caused some problems and there was a service bulletin to dealers.
 
Problem solved sort of.

Through trial and error, i figured out that the system powerup issue disappears when I remove a specific terminator. Repeated the test with every configuration...both controllers plugged in, one controller plugged in, only one terminator, both terminators..swapped terminators etc.etc...

Turns out when I remove this particular terminator from the system, everything powers up fine.

Then I tested the terminator in question and 120-121ohms between 3 and 4.....and no continuity between 4 a 5. So all good...but this terminator definitely seems to be causing the problem. No corrosion whatsoever btw. Is there some other terminal number combo I should test?

Anyway...guess I will order a new one. Thanks again for the advice.
 
You only need one terminator per bus channel. If you are using two bus channels and need a terminator; I have an extra one I can give you. PM me your address in Alaska.
 
Back
Top