Raymarine ST4000+ XTE increases

[Andrew G]

Hi, I have a venerable Raymarine ST4000+ Autopilot (connected to a SL631 chartplotter, a tiller pilot and ST60 instruments via SeaTalk1). When heading to a waypoint the XTE sometimes continuously increases (instead of staying near zero). This occurs in any conditions (light or heavy) or under motor - so it is not boat trim. My guess is a sick autopilot but do any of you have any suggestions?? Thanks Andrew

[gamayun]

I'm interested in following this thread because I have had the same problem. It doesn't always go into XTE, but when it does, I have to switch the breaker off and then power it back up. Kinda awkward when I'm single handing. Having recently purchased all new electronics, as soon as I get around to installing them, this issue is sure to go away I wish I could be of help. Looking forward to what others have to suggest. Good luck!

[Andrew G]

Hi. Thanks for your reply. Looks like we are the only ones with this problem. Cheers, Andrew

[Sea Scamp]

Hi Guys

Are you setting your pilots to follow a track or just maintain a heading, if you are just maintaining a heading your cross track error will keep growing, depending on what way the current is setting you.

Be weary of using the track setting cause soon as you reach the next way point, the pilot will alter course onto the new heading, which may not of been the best of time to change cause, at that time.

[Andrew G]

Thanks Sea Scamp. The issue I'm describing is when following a track to a waypoint. (I agree that on a heading one is at the mercy of current, leeway etc.). It has behaved perfectly for years - until now. On my system, when following a route via a series of waypoints it won't progress to the next waypoint unless you press "Track" to give it permission (without that it just keeps on the same heading). Cheers, Andrew

[Neptune's Gear]

if its on sail to waypoint, and it displays a continuously increasing XTE with a basically even (not S turning) course, the AP is faulty. take it back...

[Andrew G]

Hi Matt. The gear has performed well for more than 10 years and has only just started to misbehave (Raymarine might take it back as scrap). I'm trying to check if others have had a problem (with a fix) or whether my gear is dead (and which bit is dead - it could be the autopilot (most likely) or the fluxgate or the chartplotter) - I'm not keen to replace them all.
I'm interested in your comment about an even (not S turning) course - could you possibly expand on this?

Cheers, Andrew

[Neptune's Gear]

Hi Andrew, Almost certainly the AP computer - it is supposed to correct the XTE to 0. It's still calculating the XTE, just not fixing it.... :-(

[Andrew G]

Thanks Matt. That is what I suspected. I suppose there are no bench tests? (I can read and write Seatalk1). When I get some time I plan to pinch my brother's gear and mix n swap until I can get more evidence.
You are in the field - is there a better unit to replace it with? Cheers, Andrew