Autopilot help...

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Steve91T

Guru
Joined
Sep 12, 2016
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898
Location
USA
Vessel Name
Abeona
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Marine Trader 47’ Sundeck
So the autopilot on our boat has never worked. It won’t power up. I am going to see if it’s just a wiring issue but if it’s not, what Is involved in installling a new one? Is it a matter of just removing the old head unit and wiring a new one? Or does everything including the pump have to be changed out?

I don’t know off the top of my head the manufacture but I do know it has a digital read out. I’ve been told it’s a well known manufacture and was considered to be a good autopilot. Like I said, I’m hoping it’s just a wiring issue. But if it’s not I’d like to hear how involved installing a new one is.

Thanks
 
Really need to know what you have. Have you checked basics like power? Could be as easy as a tripped breaker or blown fuse.
 
So the autopilot on our boat has never worked. It won’t power up. I am going to see if it’s just a wiring issue but if it’s not, what Is involved in installling a new one? Is it a matter of just removing the old head unit and wiring a new one? Or does everything including the pump have to be changed out?


Could be pump, linkage, rudder reference, compass... or wiring or other physical connections...

Hard to say, without knowing more, maybe even looking at it. Not a bad job for a autopilot installer kind of guy who deals with whatever brand yours is...

-Chris
 
In general, these things involve some sensors, a computer, one or more control heads, and a drive unit.

The sensors might be a collection of individual sensors, classically including a GPS and fluxgate compass, or an integrated sensor package, such as Raymarine's EV1/EV2. It might include other sensors, such as wind sensors (especially for sail), speed sensors, etc.

The course computer takes the various inputs, including what the human would like it to do, and decides how to move the rudder. Depending upon the system's design and the type of sensors involved, the sensors may send raw data to be significantly processed by the course computer, or more baked data, e.g. NMEA. More sophisticated systems take more inputs, combine data better, can fall back to different data when sensors fail, etc.

Modern computers can interact with plotters and other devices to follow waypoints, etc.

The control head is the basic user-interface for the computer. Simple old school ones took a heading and sea condition (rough, medium, smooth). Modern ones let one monitor the input data, set more parameters, enter way points, etc.

Modern control heads are often digital and there can be more than one, e.g. one per helm. Often times, because the data is available on a NMEA bus, commands can be given via a NMEA bus, and the ability to bridge this over a network, virtual control heads can exist on a local wired or wifi network, i.e. computers or tablets running software that shows status and accepts inputs.

The drive unit is what actually moves the rudder. In the case of my present and prior boat, and I suspect yours, the steering was hydraulic, so the drive unit was a hydraulic pump that basically acted like an autopilot controlled version of the manual pumps behind my wheels at the helms. Other types of drive units are designed for systems with other types of steering. Regardless, these pumps are sized by the volume of fluid they move for the size of the boat, just like the existing pumps. In theory they might be interchangeable among manufacturers, but I wouldn't bet on it. If they were old school and on/off, probably. But, i think most now do variable rates, and I wouldn't bet on that being compatible across manufacturers.

Often times, among the inputs to the course computer is a rudder transducer that lets it know if the rudder is moving as it has asked. It provides feedback so it knows if it should try to move it more, it has already moved as requested, or it isn't moving and something is wrong. This provides feedback to the AP computer so it gets the rudder where it wants. But, like I mentioned above, I don't think it is a tight enough control loop that pumps are interchangeable across manufacturers -- but I don't know.

I'm a big fan of Occum's Razor. If your unit isn't powering up, the most likely problem is with the power to the unit (control head, computer/controller) that you are looking at. The head might be powered independently, from the same source as the computer/controller, or directly from the computer/controller, etc.

So, I'd start by looking in obvious places to see if there is an autopilot fuse or breaker. Then, I'd chase back the wire to see if there is a fuse attached to the device, or whatever the device is attached to. Then, I'd chase back to see how it should be getting power. A "ringer" (circuit tracer) is sometimes helpful in chasing circuits. There might also be internal fuses, etc.

I wouldn't worry about the rest of the system until you've gotten the power worked out. On my new boat, neither wind nor depth were working, just because someone cut wires running from sensors. My navigation lights weren't working because they were disconnected right at the upper helm. And my anchor light wasn't working -- because it was old and dead. I think someone was just cleaning up rats' nests ahead of a sale/survey and "cleaned up" a little to much.
 
By the sound of your original post it would appear that you may not be a technical kinda guy. Other than just making sure the unit has power, you may want to call an installer to troubleshoot your system as they can be somewhat complicated. Sorry if I have underestimated your abilities :D
 
Thanks guys for the help so far.

So I didn’t give you guys enough info in my original post. So this is a new to us boat and had a list of things that we needed to start checking off the list. Needed a new tach, generator needed it’s heat exchanger cleaned, stuff like that. I’m just now at the point of dealing with the autopilot.

I’ve never had a boat with hydraulic steering and autopilot so it’s all new to me.

There is a breaker for autopilot but it still won’t power up the control head. I haven’t had a chance to check the voltage going to the head unit yet.

I’m planning on going to the boat later this week and you guys are helping give me more info on how the system works and what to possible check. I’m going to check for 12 volts going to the head unit. If it does in fact have 12 volts but won’t turn on, does that mean the thing is dead? I’m assuming so.

I found this picture and you can see the autopilot cover. It’s a Simrad.

I do plan on doing the work myself. I’m mechanically inclined and will try to do the work myself.

So if the head unit is dead there might be a possibility that I can just throw a new one in there?

Thanks again. This is a big help.
 
Here it is.
 

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Looks like a AP22. Just sold one on Ebay yesterday for $550

Keep an eye on Ebay and other sites if you need a new control head.

If it is the 300X computer, send me a pm.
 
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I am more familiar with the Raymarine units than the Simrad units, but, if it is a relatively modern unit, I think the basics are the same.

There should be a "SimNet" bus, which is like a Raymarine SeaTalk-NG bus. It is basically a powered NMEA-2000 data bus. Although it is a data bus, it also supplies the power to instruments that don't demand a huge amount. For example, it'll power things like Autopilot control heads and wind sensors, but not big things like pumps or autopilot computers.

The way the bus works in the most general sense is that there is a relatively thin data cable that has some ends on it that, when plugged in, make a waterproof seal. This cable can be connected to hubs to allow it to interface devices. Some of these hubs have 3 connectors and are called Ts. Some of these hubs have a bunch of connectors and they are called hubs or multijoiners or whatever.

The upshot is that when you look at it you want to imagine a SimNet backbone with devices attached to it by spur cables. Normally, there shouldn't be open connectors -- these should be "terminated" with "terminators", basically a type of cap.

As I mentioned above, the SimNet bus is powered and supplies power to devices -- such as autopilot control heads (but not computers or pumps). So, if your control head is not turning on, it is probably because the SimNet bus, or the part that it is on, isn't getting power.

There is usually a power cable connecting to the SimNet bus. It basically plugs in like a data cable (but it is not a data cable) and powers the devices on the bus. Because it almost always shares a breaker with something else, it almost certainly has a fuse attached to it. Again, I am less familiar with SimNet, but my memory is that these power cables either have red rings around the plug side, or are attached to an integrated T-connector with red rings. The other side of the cable will be the two wires that get connected to power, hopefully via a fuse.

If your network was set up primarily for Autopilot, it probably has a simple structure. There may not even be a separate bus. In cases like this, they normally use one multijoiner (hub) and connect it to power as well as all of the autopilot related devices, e.g. the computer, control heads, rudder transducer, and the wind sensor if you have one, maybe the mutli-function unit/plotter.

But, at a certain point, once you start getting into multiple helms, more devices, etc, one hub isn't enough, and they get connected by cables, etc. Then there is more checking around to do.

Regardless, the most likely problems probably are:
1) The control unit got disconnected from the SimNet bus
2) The SimNet bus's power cable got disconnected from power or the fuse is missing or blown
3) The SimNet bus is disconnected somewhere between power and the control unit.

If you've got other small insturments connected to SimNet, such as a wind speed gauge, that might give you a hint as to whether or not some part of the bus is getting power.

You might also be able to pull apart the connections and test for power along the way, such as right at the control head. This looks like the pin out:
-- https://seatronic.no/media/catalog/...3525d08d6e5fb8d27136e95/s/i/simnet_tig_03.jpg
-- Article Details

With the "key down" it looks like red is to the left and black is above red.

Hope this helps!
 
I am more familiar with the Raymarine units than the Simrad units, but, if it is a relatively modern unit, I think the basics are the same.

There should be a "SimNet" bus, which is like a Raymarine SeaTalk-NG bus. It is basically a powered NMEA-2000 data bus. Although it is a data bus, it also supplies the power to instruments that don't demand a huge amount. For example, it'll power things like Autopilot control heads and wind sensors, but not big things like pumps or autopilot computers.

The way the bus works in the most general sense is that there is a relatively thin data cable that has some ends on it that, when plugged in, make a waterproof seal. This cable can be connected to hubs to allow it to interface devices. Some of these hubs have 3 connectors and are called Ts. Some of these hubs have a bunch of connectors and they are called hubs or multijoiners or whatever.

The upshot is that when you look at it you want to imagine a SimNet backbone with devices attached to it by spur cables. Normally, there shouldn't be open connectors -- these should be "terminated" with "terminators", basically a type of cap.

As I mentioned above, the SimNet bus is powered and supplies power to devices -- such as autopilot control heads (but not computers or pumps). So, if your control head is not turning on, it is probably because the SimNet bus, or the part that it is on, isn't getting power.

There is usually a power cable connecting to the SimNet bus. It basically plugs in like a data cable (but it is not a data cable) and powers the devices on the bus. Because it almost always shares a breaker with something else, it almost certainly has a fuse attached to it. Again, I am less familiar with SimNet, but my memory is that these power cables either have red rings around the plug side, or are attached to an integrated T-connector with red rings. The other side of the cable will be the two wires that get connected to power, hopefully via a fuse.

If your network was set up primarily for Autopilot, it probably has a simple structure. There may not even be a separate bus. In cases like this, they normally use one multijoiner (hub) and connect it to power as well as all of the autopilot related devices, e.g. the computer, control heads, rudder transducer, and the wind sensor if you have one, maybe the mutli-function unit/plotter.

But, at a certain point, once you start getting into multiple helms, more devices, etc, one hub isn't enough, and they get connected by cables, etc. Then there is more checking around to do.

Regardless, the most likely problems probably are:
1) The control unit got disconnected from the SimNet bus
2) The SimNet bus's power cable got disconnected from power or the fuse is missing or blown
3) The SimNet bus is disconnected somewhere between power and the control unit.

If you've got other small insturments connected to SimNet, such as a wind speed gauge, that might give you a hint as to whether or not some part of the bus is getting power.

You might also be able to pull apart the connections and test for power along the way, such as right at the control head. This looks like the pin out:
-- https://seatronic.no/media/catalog/...3525d08d6e5fb8d27136e95/s/i/simnet_tig_03.jpg
-- http://support.simrad-yachting.com/...ZONE_OFFSET=&CMD=VIEW_ARTICLE&ARTICLE_ID=2733

With the "key down" it looks like red is to the left and black is above red.

Hope this helps!
 
Okay. Sorry. I *think* that is an older unit than I expected. It *think* it probably dates to the late 90s or early 2000s. I apologize for speculating in my last answer -- and now

In those systems, as best as I can remember -- and I am stretching here -- there was a control unit that also acted as the junction box for all of the wiring. The power attached to it via a breaker or fuse. And then, everything else attached to different terminals on it, even the pumps, etc. So, the circuit breaker you found should power it. And, it should power everything else. I know very little about the details.

My memory is that some devices, like the pump, always connected directly to specialized terminals on it. And some devices, like control heads were daisy-chained off of the ROBNET (Robertson Network) terminal on it, ROBNET being a multi-drop RS485 connection of some kind. I don't know the pinout. And, some devices, such as compasses and heading sensors came in different versions, some of which connected directly to specialized terminals and some of which daisy-chained on the ROBNET.

Regardless, what you are seeing is no power at a control head. So, I'd first check to make sure that power is getting to the control unit. This should be as easy as putting a meter on the power supply terminals on the unit itself. These are typically easy to find. I think they are the left-most connections -- and the wires tend to be the biggest.

Then, from there, you want to go over to the other stack of terminals, normally farther left, and you should find the ROBNET terminals. Hopefully you'll see grey, pink, brown and white wires there. I *think* grey and pink are one pair and brown and white are the other pair. I *think* Grey/Pink provide the power and black/white provide the data. So, I'd look for voltage on grey and pink first. Then chase it from there to the control head. If you look at a /cable/ with the notch up, I *think* the power pair are the two to
the left, the data are the two to the right, and the two in the middle are out-of-band to signal an alarm.

Again, I think the most likely thing is that something is just disconnected from power, so I'd start with the control unit and make sure it is getting juice. Then, I'd unplug the control head and check the cable to see if it is getting juice -- I'd bet not. Poke around with a voltmeter, in case I have the pins wrong. Then work back from there to the control unit to see where the power is lost.

If the control unit is getting power, but not powering the bus, I'd bet on an internal fuse. At that point, you'll need to find a service manual or take it a part and see if you can find it. It could be traditional, or built-in. Again, a voltmeter is probably your friend. There might also be some LEDs that'll give you a hint.

If the control head is getting power and not turning on, I'd probably try to buy another on eBay. If one can be had, it is probably worth the risk. If not, well, I'd take the control head apart and look for an internal fuse or blown diode or something there. I don't know how serviceable those are. Maybe there is a service manual that can be had.
 
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I guess it is worth me saying that I really don't know exactly what type of Autopilot that is. I just took some guesses. But, I think the common debugging path is worth noting.

1) Check to make sure the head is connected to whatever cable is behind it.
2) Find out how it should be getting power and is turned on if there is a switch and look at that device (hub, controller, etc), and make sure it is really getting power in use meter or check lights).
3) Then make sure it is really putting power out. Looks to see or research which terminals or pins carry power and check to make sure that they have it.
4) Spy as many of the connectors along the way to the control head as you can and make sure they are connected
5) Research the pinout for those connectors and see where power is lost using a meter.
6) Address wherever the power is being interrupted (circuit breaker, external fuse, disconnected wire, cable with bad pin, loose or disconnected connector, internal fuse, bad internal component, etc)
 
I guess it is worth me saying that I really don't know exactly what type of Autopilot that is. I just took some guesses. But, I think the common debugging path is worth noting.

1) Check to make sure the head is connected to whatever cable is behind it.
2) Find out how it should be getting power and is turned on if there is a switch and look at that device (hub, controller, etc), and make sure it is really getting power in use meter or check lights).
3) Then make sure it is really putting power out. Looks to see or research which terminals or pins carry power and check to make sure that they have it.
4) Spy as many of the connectors along the way to the control head as you can and make sure they are connected
5) Research the pinout for those connectors and see where power is lost using a meter.
6) Address wherever the power is being interrupted (circuit breaker, external fuse, disconnected wire, cable with bad pin, loose or disconnected connector, internal fuse, bad internal component, etc)

Thank you so much. That’s all a huge help. I’ll mske sure to reference this when I’m down there trouble shooting.

I do believe it’s an older unit.

Thanks again!
 
It is a Simrad AP22.

Anyone know which pin is 12v and which is ground so I can see if this thing is getting power?
 

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It is a Simrad AP22.

Anyone know which pin is 12v and which is ground so I can see if this thing is getting power?
Looking for power is easy. DC Volts scale; touch the red lead to the top pin then the black one at a time to each other pin. Nothing, move the red lead to the next and touch each other pin, etc, etc. Only takes a couple minutes.
 
I don’t have any voltage at the pins.
 
Okay, so those are the pins at the control head? Back up to the junction unit and see what is going on there. It is a box that looks something like

221c7ff3-21e0-4d3d-b0cf-7193355f1880_1024x1024.jpg
this
 
Okay, so those are the pins at the control head? Back up to the junction unit and see what is going on there. It is a box that looks something like

221c7ff3-21e0-4d3d-b0cf-7193355f1880_1024x1024.jpg
this

Thank you for that pic. The cable runs downstairs so I’ll look for that.
 
Here it is
 

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Here it is

Okay. So the bottom black piece unscrew to reveal the place where the wires are screwed in. Unscrew it. Check to see if it is getting power.

The power wires are normally, to my memory, the left most 2 wires, but, the colors and positions here arent giving me confidence that it is the case here. You'll see when you open it.

The terminals might be labelled. But, there are probably only two pairs of relatively fat wires. One to power the junction box and the other for the box to power the pump. Control heads and rudder sensors etc are much thinner.

To my memory the left two, TB1 and TB2 are the power and TB3 and TB4, juat to their right are the pump.

Is the junction box getting power? Can you measure 12V across either pair of fatter wires?

If so, look for RobNet power. It should be on thebother group of terminals to the right....it may be labelled TB15 or Robber. Look all the way on the right. Measure across the pink and grey wires. Counting from the RIGHT they may be positions 5 and 4. Look for 12V.
 
The joys of a new big boat, keep knocking the problems out one by one. Good luck.
 
The joys of a new big boat, keep knocking the problems out one by one. Good luck.

Ehh, I enjoy it. Finally starting to learn my boat.

Let me rephrase that, I enjoy relatively simple, inexpensive things. :)
 
Friends are here, going to have to wait till later.
 
Well friends on the boat means more help for you, put them to work.
 
Hello all! Finally back at this. I can’t get any voltage anywhere. The big wires either go to the flybridge or down to the engine room.

Tomorrow morning I’ll see if I can track down those wires but I kinda thought I’d be able to find the power wire under the lower helm which is where the breaker panel is.

Any ideas?
 

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