Drive Unit Error on 711C / FAP7002

[seaveepete]

30' Twin outboard center console, with 7 year old 711C/FAP7002/PG700 setup.
AP has been working fine for years but lately as soon as I power on the 711C I get the error below:
Drive Unit Error Please turn off and check drive circuit

I've tested the pump in isolation and it works fine. The PG700 gives me good heading info too.
There is no air in the steering system.
I called Furuno support about this 2 weeks ago and they wanted me to reset the unit to factory defaults which I did.
No change - still immediately get the error above when the unit is powered on.
Does this error mean that the FAP7002 processor unit is dead?
Is there an internal fuse in that unit that I can check?
I would appreciate some advice on EXACTLY what generates that error and what to do next.

Thanks,
Pete
-

 

[seaveepete]

Anyone?

 

[Kraken]

Drive unit error is usually an alarm concerning either the pump or the hydraulic system. It could be air in the hydraulic lines, bulging hydraulic lines or a power issue with the pump. We would recommend that you power purge the hydraulic lines and check all the hydraulic lines for worn or damaged hoses.

 

[Johnny Electron]

If your RRU goes bad or slips it can fool the pilot into thinking there an issue as well. Check that your RRU is reading and moving correctly.

 

[seaveepete]

Thanks guys but let me answer a few of the questions raised here...

1. The hydraulic system and plumbing including lines, steering cylinder, and helm are all in perfect condition and there is no air in the lines. Note that I'm a marine electrician and also install autopilots and other steering system components. I also have a Seastar PowerPurge Jr. and have purged the steering system on my boat so there are no issues there.
2. Re: the pump, I have tested it in isolation and it runs fine, it's quiet, and also works in both directions when I reverse polarity on the pump leads. The motors move easily in both directions during this test.
3. Re: the RRU comment, this is an outboard boat with fantum feedback so there is no RRU.

The other thing to remember is that the Drive Unit Error happens IMMEDIATELY when the system is powered on - NOT when I try to engage the pump.

 

[Johnny Electron]

Have you tried updating the software to the most current version? If this is a very old pilot, I do recall a software bug that people could trip into that would cause that error. If not running the newest software, I would try that next.

 

[seaveepete]

Sure, I understand the recommendation to update the software but I seriously doubt that will make a difference.
Nothing was changed on the network and no settings were changed before this error started happening.
What I really need to get from Furuno is the root cause behind that error message. Someone on the software side of the house should be able to provide that info.
Again, this error happens immediately when I power up the 711C control head.

 

[Johnny Electron]

If happening on power up you likely have a damaged circuit. Please send the unit in for repair evaluation.