Trolling motor problem

Discussion in 'General Electronics Chat' started by electronis whiz, Jun 21, 2014.

  1. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
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    My dad asked me to look at some stuff on his boat. I don't think was used a lot last year. This year it's having issues, all electrical related.

    main engine had some issues and would start. went to test trolling motor thinking well if engine has issue again there will at least be something other than oars to get back with.

    It's a larger minn kota power drive motor, fish finder sensor, control pad for all the controls even steering. Some reason the motor plugs into a port on the boat, control pad has own interface too. I tested using the battery gage on the motor to see if had power, nothing. disconnected line from battery to plug, and used fine file to get the corrosion, etc. off. Used file to do same thing on the motor plug, and the control pad connections, as nothing was working. I did that until looked to be quite clean. Then I got the steering part working, but the drive motor wouldn't activate. I checked the connections, all was fine, so I popped open the base unit, and looked at controller.

    Area around controller board was full of spider webs, etc. I tested for voltage in and out of board. Input was fine, but no output even when I pressed the full speed pedal n the control panel. That made a relay trip, but no output. Checked the terminals, filed off until were clean still nothing.

    I want to say the control boards shot as the full speed button fails, and the just trolling, and speed adjustment also fail. The speed control I think is a PWM setup, which tells me A something's up with a connection, which I doubt or the boards fried. I doubt connection as were clean, and relay tripping, but no output tells me something's up in the board. There's no way to fix the board as is all covered in resin (or something plastic like).

    Looks like you can get just the control boards for like $75 USD, but because had issue with connections I'm not 100% sure that is the issue, or only issue.

    Kind of looking for tips either things I may have missed, or just an idea my guess is correct. I find odd how 2 yrs ago it worked fine, all the sudden something like controller fails. I'd kind of like to test the motor directly just see if maybe something isn't shorted out, and that fried the board. Not sure that's ok to do though, I would guess the motors basically like what they use for starters, or tilt/trim, simple 12V DC motor of some sort. (only 2 wires, so seems like only thing could be.)
     
  2. Brownout

    Well-Known Member

    Jan 10, 2012
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    Sorry to hear that. That's a complicated trolling motor. Mine just has a rotation switch for low, med and hi. But I guess your father's is an infinite speed type. In that case, the board is probably just a PWM controller, and that should be pretty simple to t-shoot. Is it possible to get a schematic?
     
  3. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
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    I hadn't thought of getting a schematic, but could be possibility, but I doubt minn kota publishes that stuff. I'm pretty sure this is PWM, as on the side of the board there was 3 transistors or mosfets (not sure which) screwed to the metal mounting platform for the motor. The control pad has a tilt pedal for steering, a momentary press for full speed (activates relay on control board. Then there's an on off switch associated with a sliding 0-10 speed adjustment. I couldn't get the constant drive PWM to do anything either. From what I could see the + from source, and motor are linked. The - are separate, and no mater what the output - will not register any voltage even if relay trips.

    Relay could be simple fix, were not cast in plastic, and also the PWM appears to be dead tells me there's something major up with it. I didn't see any fuses on it either. The motor was with boat when we got used about 4-5 yrs ago. I can tell the original one from the factory was replaced as current one is spliced on to the plug from the original. Kind of tells me that these motors may not last all that long before something major happens. I don't expect more than few yrs life from something like that due to environment.
     
  4. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Can you test those? Do they have any identification markings?
     
  5. inwo

    Well-Known Member

    Nov 7, 2013
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    Need a picture, model number, schematic. Anything?

    Fixed one last year that had a shorted (and burned off) cable to motor, Where it swiveled and went down tube. In the top "box" part.

    The ones I've worked on were dc motors that can be test with low dc voltage.

    There must be a fuse or breaker some where to protect controller and motor when jammed.
     
  6. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
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    I don't think I could test the transistors, as the entire board was encapsulated in plastic stuff.

    I thought maybe a fuse, but didn't see anything. I kind of remember one being by the back by the batteries, but got busted when we swapped batteries. Nobody local seemed to stock the size fuse, and holder, so we just spliced. Up by the control unit I didn't see anything looked like a fuse. some heat shrink on some connections, and unused leads. Going to try and test motor, think use 30A relay I have, as I don't have switch that size, and am leery of just touching terminals together.
     
  7. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
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    I just went over, and looked at, pulled board so we can find a new one. I tested the motor just totally removed controller, and linked wires, and other I put in a relay with push button. soon as I pressed relay button motor took right off. So appears motor is fine, tested control pad contacts also fine.

    The motor is a minn kota 55PD, board don't seem to have any info written on it. I wasn't totally sure at first was removable, as looked like the transistors mounted to the frame. Actually a small heatsink, then that screws to the frame.
    I'm going to use my ohm meter and test the control pad buttons, but my suspect is the control board. I didn't see any signs of bulging caps, or anything fried, or odd smells.
     
  8. inwo

    Well-Known Member

    Nov 7, 2013
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    All it takes is a reverse touch when connecting batteries or jammed motor to fry something. It needs a fuse.
     
  9. bwilliams60

    Active Member

    Nov 18, 2012
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    Can you post any pictures of what you are working on/with? I have some marine electrical experience and may be able to help if you can show me what it is you are doing? Pics of controller, motor etc.
     
  10. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
    519
    27
    I know I was just thinking about adding a fuse in while I'm at it. Worst case use a auto fuse, and some spade terminals, and tape it up. Not sure what A to use though. I think 30 would do.

    Here are some pics of the control board. I didn't think to get any of the motor. Motor is fairly simple input power, battery tester, control board on the base, bolted to deck. The motor deploys on a pivot so stores laying sideways. In that there is a motor for steering, and a adjustable clamp that locks to the steering motor. A coiled cable linking base to the motor to the base. Also a "8 pin" (7 are used) connection to the control foot pad. that does steering, speed, on off, etc.
     
  11. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    It would help if the pics were in focus so that we could read the text and see details ;)
     
  12. inwo

    Well-Known Member

    Nov 7, 2013
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    If it's any help.
    A short circuit damaged the one I was talking about.
    Same symptoms.
    A new board fixed it.
    Money wasn't an object, so I didn't trouble shoot board.

    Found the old one.

    The middle two power devices are IRFZ48N.
    The one close to the "I" has hole burned in the face.
     
    Last edited: Jun 23, 2014
  13. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
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    I had thought about looking into, but being all sealed, and PWM I don't see worth it. Also don't have tool to test mosfets, all the caps seem ok.

    Sorry pics weren't that good used my phones camera. The model I believe is 230-4043 rev C. Simpler just replace the board, then I know should work, and last more than maybe a year or 2. I pulled the battery tester PCB too, as one of the connections was heat shrink covered. I think I'll have to cut the heat shrink and probably move that to the new board once that's ordered.

    I did some minor touchup work to the pedal too. Was all dirty under the covers, and one of the switches has a lever arm, that was a little out of position so wasn't always tripping the button on the PCB. Even with pedal functioning fine (verified with ohm test board wouldn't put out any current.
     
  14. bwilliams60

    Active Member

    Nov 18, 2012
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    Is this a Minn Kota Powerdrive Version 2 by any chance. I have a schematic somewhere if it is. What is the main problem? Nothing works or the motor doesn't work?
     
  15. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
    519
    27
    I'm not sure of the version to be honest. the replacement boards I'm seeing say 2001 and newer. Which fits as boat is an early 2000 model, and motor appears to be a replacement, as cord is spliced into the original 12V plug. The steering motor works fine, but that's basically a simple DPDT switch in the control pedal. The main motor does nothing. (tested motor that's fine)

    I press the either of the on switches on the pedal the relay sounds like it trips but nothing happens, same with the variable speed PWM part. I even ran with boat on the hoist and motor in the air so I could see, and be less load. No matter what I tried the board wouldn't do anything besides make the relay trip.

    I'm not sure the pwm part uses the relay as like on/off or if setting to speed to 0 does that. If uses pwm on/off too may well be bad contact in relay.

    Even if I had idea how to fix I still have no idea how I'd get the plastic covering off the board. Appears to be like hard plastic, not like a glue or something.
     
  16. bwilliams60

    Active Member

    Nov 18, 2012
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    From your description of the problem and my schematic, it sounds like a board problem and as you say, it's dipped in epoxy so you are not likely to get at the components. All marine electrical units must be sealed to prevent explosions from fuel vapors. Unfortunately, big price tags also come with that safety but I believe you can pick one of these boards up for just over $100. The parts number should be #2884056. Is there any voltage coming out of the red and black plug in wires (heavier) a the top of the board. Will they light a headlight or fan motor? Can you jump the wiring to 12V from the board and make the motor work? Lastly, is the foot pedal a potentiometer? Do you have B+, B- going to it and a signal from it to the control board? Just some thoughts.
     
  17. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
    519
    27
    I tested for power in, and out. I took apart the pedal, verified that PCB, all looked ok, I pricked the wires on the board, and solder link on the control pad all showed connection. I tested the motor just slit the 2 + spade terminal into each other, and - I linked to a 30A relay I had. I tripped relay the motor ran. To me it's got to be the board is bad.

    Best guess is relay on board has failed, but not something easily replaced. we got a new board ordered for about $80. I'll just have to put in when we get it. If old board is just going in trash I may try and see if can't some how remove the plastic and try and fix even if it's for a spare. maybe use dremal or something to get off. I damage the board oh well it's junk anyhow. If I get working just put some calk or something on it.
     
  18. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
    519
    27
    Mission accomplished. Got new board ordered last weekend came in mail today. Was like $80 for new one. Installed new one tested it works, looks like that was the problem. I felt pretty confident it was, but never having worked on one before wasn't totally sure.

    Thinking about taking old board apart, see what I may be able to do. Think use dremel or something cut the plastic stuff off.
     
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