Logo
FULL SITE MENU

BF50 remote trim switch blows fuse

A

amberjack

New member
Hi guys,
I have a 2005 Honda BF50A and had some problems this summer with trim/tilt switch. First the battery died but it was very old and it was high time to change it anyway (I guess the switch already started shorting and that finished it off). When I installed the new battery using remote control trim switch started blowing fuses (I think it was the 15 amp one) and after I changed a couple while testing this, it even started smoking a bit around the engine connector bracket (on the side of the engine below the black perforated plastic cover). As all this was happening just when I started my vacation :) I removed the cover and figured out how to disconnect the remote switch and rewire it so only the switch on the engine could be used. I asked around and they told me it could be either the switch or in worse case the wiring harness which can only be completely replaced and is very expensive, business as usual :D I tested the switch and it seemed fine, in the end I left it disconnected like that and only used the switch on the engine.

Recently I had to disassemble everything on the boat anyway so I figured I'd check this out, brought the remote control and the wiring harness (the cable from the engine with 3 connectors on controls side and a big round one on engine side) home and tested it with an ohmmeter. First I checked the 3 wires from the switch (Lb, Lg and W/Bl on the wiring schema) on the controls connector and there are no short circuits between these 3 and any other pin on the connectors. When switch is pressed it connects W/Bl to Lg (up) or Lb (down) as specified on the schema. Then I checked the cable and again couldn't find any short circuits between one of these 3 wires and any others. Any ideas what the problem could be and what else should I check ?
Thanks in advance.
 
Look in the handle of your shifter. You did not say if the fuse blew by pushing the up or pushing the down button.

If the fuse only blows when pushing the switch, then either the Lb or Lg leads have been nicked or cut inside the shift handle or more likely where it comes out of the bottom of the handle. The positive voltage traveled through the metal of the handle to the throttle/shift cables, back to the engine or possibly the frame of the shifter to your boat (if it is metal) back to the engine.....seeking ground through the engine mounts....burning the small bonding strap that you referred to .

I think, if you pull your shift handle off and examine the trim/tilt wires, you should find your answer. The wiring is supposed to wrapped around the base of the shifter handle a certain way, so that it does not pull or bind....however, many who take their handles off do not know to put it back the correct way. I have seen several rigged wrong from dealers too.

Happy hunting.

Mike
 
Thanks for the idea, I didn't think of that possibility before. I disassembled the remote and the shift handle but couldn't find any damage to the wires or the black sleeve they are mostly covered with. Also couldn't measure any short circuit between the wires and metal parts of the shift mechanism.
As for the up or down button I'm not 100% sure but I think either had blown the fuse, the boat is plastic (rigid hull inflatable) so no possibility of short circuit with the hull.
I'd be grateful if you have any other ideas where to look, not sure what else to do.

Thanks
 
Ok..no metal boat.....so much for that theory...

A few questions...it sounds like you did most of the obvious checks.

1. What shifter do you have? Is it a side mount box with a key in it? Binnacle mount on the top of the console. Or concealed side mount?

2...You said you blew the 15 amp fuse. Are you sure it was not the 10 amp fuse (which is the one that feeds the trim switch on the shifter). The 15 amp feeds the trim switch on the engine.

3..Did the fuse blow when you had the shifter in gear? Or while shifting?

4. Did the fuse blow with the motor running or was the motor turned off?


Mike
 
1.The standard side mount with key that comes with the engine by default.

2. I'm not sure about the fuse, it was some time ago, actually it might have been the 10 amp one.

3. I don't think it was affected by the shifter at all, just the trim switch.

4. That's a great question, I seem to remember initially it just blew just when the engine was running but it got progressively worse as I tested it (and changed fuses), blew even with the engine off and in the end started smoking. Actually I think I ran out of fuses and put in one with a higher rating (15 amp?) and that's when it started smoking. Yeah, I know that wasn't the smartest thing to do :eek:

Thought it would be easier to find the cause once everything is disconnected and I don't have access to the engine right now as I left the boat for some hull repairs, should be back in a week or so.

Thanks
 
This is very puzzling. The Lb and Lg leads are common for both the trim switch on the handle and the trim switch on the engine. But you say, there is not issue when you use the switch on the engine. The only difference between the two switches electrically is the 12v source. So, I would then have to make the assumption that my theory of one of the Lb or Lg leads being shorted to ground, causing the problem to not be correct....

Back to the shifter.....

If your shifter is like any that I have put on an inflatable, it was probably mounted on the right side of the console. In order to do that, the handle had to be moved from the standard side of the box to the other. In doing so, the trim switch leads had to be rerouted. If the person who did it, did not route the leads properly and under the plastic shield, they could rub on any of the moving parts inside the shifter.

So, I would relook at the shifter and the trim switch wiring and the pig tails that leads attach to. The short to ground may only occur when in gear...

One other thing...and this is really a stretch....could the switch have an internal short...if so... when the switch is operated, it tries sends 12v on both the Lb and Lg leads at the same time. I am really not sure what this would do. Check for continuity between the Lb and Lg leads when you operate the switch.

That is all I have at this time.

I will continue to scratch my head.

Mike
 
I'm scratching my head too :D
You are totally correct about the shifter, I installed it myself on the console and moved the handle to the other side. But I don't think I messed up, don't have too much experience with all this so I try to analyze how everything fits and be careful, I think I routed everything like it was originally. Anyway I rechecked and couldn't find any signs of damage to the leads, measured resistance between all possible combinations of pins on all connectors (and on the main engine connector with the cable connected), with the switch on (up or down) and off...
I guess the only thing left is to wait until I get the boat back, connect everything to the engine and battery and see what happens, just hope I can remember how to rewire everything back on the connector bracket :)
The only options left I can think of are that there is a short circuit somewhere by the engine (between the main connector and the bracket where I rewired the leads) or somewhere in the cable but only when it's wet (wires with damaged isolation but not in direct contact without seawater) :confused:
By the way I work as a software developer and debugging is always the trickiest part, guess that's similar in any line of work :rolleyes:
 
Yes, it is probably pretty close. It may be more like...you have a perfect running program and someone puts a line of code in it that screws things up. You just have to find that line of code and the problem is resolved. AKA....where is that needle in the haystack!

You probably have a point...if you can not find anything apparent in your continuity testing, then when you put things back together, start with the lowest common denominators. Only connect the motor to the battery....no accessories. Then only connect the main wiring harness to the engine and the control box. Do not even connect the throttle/shift cables at that point. Make sure you have the correct size fuses in place...then give it a try.

Try to think of what may have been changed or added to the boat since the trim worked correctly.

Mike
 
Got the boat back, spent better part of the day today putting everything back. At each step tested the trim switch and it worked perfectly. In the end when everything was connected I tried to turn the key to on position and try then, also no problems. Just thinking about how I don't like things mysteriously repairing themselves, with my luck it will probably give me trouble again later on, but ok better that it's working, lets just try turning the engine on.... turn the key and nothing happens :eek:
The starter doesn't give any sign of life at all, at first I thought maybe the shifter wasn't in neutral or the 15 amp fuse is blown, checked both and nothing :mad:
Trim still working perfectly, the only detail I'm not sure about is that the instrument only shows trim level when the key is turned to on position (don't remember if it was like that before but I guess not related anyway). It was getting late and I was getting close to a nervous breakdown :eek: so decided to leave it for another day and ask for your advice.
I need to figure out the easiest way to check if starter motor is getting any power (I was alone so couldn't use the voltmeter at the starter and turn the key at the same time, really don't want to pull all the cables back again) but my suspicion is on the shifter, I know it has some kind of protection that works just like this when it's in gear, maybe I messed it up somehow with all this poking around ?
 
I replied last night, but I guess it got lost somehow...

It may be possible that you cleared the trouble by taking it all apart....but who knows?

A few things to look at first regarding the starter.

The shifter does not have a neutral safety switch, but the engine does. First make sure that the engine is really in neutral. Can the prop spin freely both ways? Make sure that the neutral safety switch at the front of the engine is depressed by the shift linkage detent. If not, you should just have to readjust the shift cable connection at the engine. I am not sure how you connected the throttle/shift cables, but you connect them at the shifter first, then make the necessary adjustments at the engine.

Tracing back from the engine....there is a black/white lead that goes from the starter, to the bullet connector crossconnect on the port side of the motor, to the neutral safety switch connector, through the neutral safety switch, through the wiring harness to the 14 pin connector on the front of the engine, then thru the main wiring harness to the shiftbox/keyswitch.

To test just the starter, you can go to the crossconnect and disconnect the black/white lead bullet connectors and jump it to 12v. You just need a small wire (it does not draw much current). I usually use a starter switch connected there to do compression and spark tests without needing someone to operate the key.

One of the most common problem areas, other than the motor not being in neutral is a pin that was broken or pushed back in the 14 pin connector. So recheck all the places you touched and disconnected things.

Mike
 
Thanks for all your help, don't know what I would do without it. The problem was with the safety switch, it wasn't fully depressed by that black plastic lever connected to the shift mechanism, guess that's the shift linkage detent. Wasn't sure how to adjust for that so I experimented a bit and realized I needed to unscrew both the shift pivot on the engine side and the eye end on remote control cable end to push it fully. In the end I had to unscrew it pretty significantly (not sure if the cable is required 8mm in the eye end and it's not protruding from the pivot at all) to get it working reliably, not sure if that's ok and if there is a better way to adjust ?
Trim works perfectly for now, still have to connect the rest of the stuff (lights, bilge pump, gps, fishfinder) and see if that causes any problems, not sure if I should hope that it does or not :)
 
I am not exactly sure what all you did. All you should of had to do was remove the part #80 http://www.boats.net/parts/search/H...005/BF50A5 LRTA/REMOTE CONTROL (2)/parts.html

from the shift arm and screw or unscrew it on the shift cable to adjust it. If you could not unscrew it enough without it coming out of the pivot, then you have to give yourself more tread by going to the shifter and backing the cable out of the pivot at that end.

Mike
 
I looked at the service manual to see how all the parts are called and what's the proper adjustment (http://************/lib/honda/manuals/bf40bf50.html#/180), just a bit worried that I had to unscrew quite a lot on both sides (both parts #80 and #17 on your diagram) to give it enough push and now it's not according to specs in the manual (pages 181 and 182, it says that cable thread should be going more than 8mm into #17 and it's a bit less than that and that it should protrude 5mm out of #80 and now it's not coming out at all). Not sure how important those specs are and if there's a real chance that something could come loose?
 
It seems now it's my turn to have a post disappear :)
I replied this morning, but don't see it any more. Basically I looked in the service manual (http://************/lib/honda/manuals/bf40bf50.html#/180) to see how the adjustment was done and the specifications there (pages 181 and 182) are that cable thread should be screwed in part #17 at least 8mm and that it should come out of the pivot (part #80) about 5mm. I had to unscrew both parts #17 and #80 to get enough length that neutral switch was reliably depressed each time and the thread is barely 7-8mm in part #17 and not coming out at all from #80, just checking if that could be a problem and if those specs are really critical ?
 
Seems I'm having some problems with posting, at first I didn't notice what happened but when I tried to post again I noticed the message that my post needs to be approved by moderator or something like that :confused: Maybe that was because of the link to bf50 service manual, you probably know where to find it or have it already so I'll skip it now.
So let's try again, I looked in the service manual (page 181-182) and it states that cable thread should should come out of the pivot (part #80 on your schema) about 5mm and on the other side enter part #17 at least 8mm. I had to unscrew both to get enough length for neutral switch to be fully depressed so now cable thread is not coming out at all from #80 and I think a bit less than 8mm in #17, just wanted to check if that could be a problem and if those specs are critical ?
 
You should be good. I have found that those measurements are good starting points.....as long as you have the cable sufficiently through the pivots.

Sometimes you have to take some away from one end to give to the other.

A suggestion for others, whom may be reading this besides us.....connect the cables at the shift box first and do not permanently install the box until you are sure that there is enough cable at the motor end to make final adjustments for shift and throttle. Otherwise, you will have to continually remove the shifter from it mounting and do it again. It saves a lot of cuss words.

Mike
 
Good advice, If only I knew all this before it would have definitely saved me a lot of trouble and a lot of swearing too :D
I'll finish connecting everything this weekend and test again then, hopefully the trim issue will not happen again. By the way I found one wire with damaged isolation but it's just for the stern light, don't think that had anything to do with it but will replace it anyway.
Once again thanks for all, a shame you are too far away as I owe you at least a few beers :) If you ever happen to go for a vacation in Croatia let me know :cool:
 
Back
Top