Stumbled onto an Electrical problem. Need help and opinions

[Midnight]

Hopefully this isn't to longwinded. I have a 2007 Venture with 72000 miles on it that I have owned since new. Bike has been an amazing machine. This site and its members have helped me so much in maintaining it and managing its quirks.

I'm hoping the electrical experts can chime in and help me work through this.

I have noticed for sometime that the factory horns didn't seem to be as loud as they once were and seemed very week. I removed the one on the side of the bike and hooked it directly to the battery. It works fine.

So I started checking out a few things and stumbled onto this. What I discovered was I had 12.6 volts at the battery and 11.6 volts at the brown horn wire to ground when the key was selected on. When the engine is running I have 13.6 volts at the battery and 12.6 at the horn. So I am losing 1V somewhere in the system.

The bike starts and run perfectly so I suspect the charging system is working fine.

It seems that I have approx. 1V voltage drop somewhere between the battery and the horn load.

So I checked voltage at the fuse block under the side cover with the key on bike not running. The headlight circuit is 12.6 V. The signal(horn) circuit is 11.6. And the ignition circuit is 11.6 as well. So I am losing 1V in more than one circuit.

Looking at the the wiring diagram it is clear that all the load passes through the key switch. I have yet to remove the tank and check all the connections/voltages at the main/key switch but that seems to be a possibility of where the voltage is being lost. I plan on removing the tank and going there next.

I have had the main key switch apart once and visually checked the tumbler, soldered joints and circuit in the key switch. It all appeared to be fine and there were no signs of overheating at the connections. That was about a year ago.

So I'm wondering if anyone has any suggestions or experiences with this or something similar. Is the main key switch on its way out? I know there is a relay "plug in" system a member makes here and I plan on looking into that. I would like to track down and solve this voltage drop first.

Many thanks to whomever wants to chime in. JR

[garyS-NJ]

I'm loosing almost a volt through the key switch also

[Flyinfool]

It is common to have 2nd gen ignition switch issues.

That is why the plug in relay system was developed in the first place.

It should be pretty easy to isolate the source of the 1V drop.

 

Eventually that 1V will become more until stuff stops working correctly.

[cowpuc]

Well,, I am no lectrician like a lot of these geniuses but it seems to me that resistor's are used in electronics to control/change or manipulate voltages. Of course, most resistor's used in electronic's are little gizmo's filled with who know's what (engineer's who design those things are some crazy people - only they know for sure whats inside those things). Only reason that matters at all to me in your case is cause everything from corrosion in a circuit board to broken wires to dirty contact points in a relay to a loose connection can cause resistance = resistance is resistance = its all about resistance.

I think if it were my bike Middy I would get out my Ohm meter, make some kind of a long reach probe with a real sharp point on it and just start tracing wires looking for the source of that resistance. Gotta be a Before = 1 volt higher - than after connection = 1 volt higher in there somewhere.. Just connect the ohm meter direct to battery ground so ya got a good known ground and go to poking into wires leading into the horn area. Schematics can be a good help cause they are excellent electrical road maps (not trying to funny - just seems that way to me) but I have solved a number of electrical issues like your talking about without one just by probing with a probe. Another thing I learned (and have had to learn many times over cause I am pretty stubborn) is that isolated grounding issues can also cause the problems (I am thinking resistance doesn't really care where is located in a circuit - can still have the same affect).. Maybe take a test cord, just for kicks, and from the horn ground back to the battery and see if that helps..

 

My thats probably only worth half that,, or even less:big-grin-emoticon:

[Midnight]

Thanks for the comments. I plan on doing voltage and resistance checks heading up to the main key switch and around the switch and go from there. Also sent djh3 an email about the relay and bypass switch he makes as that would compensate for the switch???

[videoarizona]

Sounds like a good plan, Jim. Puc is right, you probably have some corrosion somewhere common to the two circuits that have the voltage drop. Like maybe the run switch or something like that. Resistance will show you the problem.

Good luck and let us know what you find! I'm at 50K miles and did buy djh3's bypass relay and installed it...just in case!

[djh3]

Also the power wire for the switch at the bike harness has been known to corrode or the connection go bad. Then because of the larg draw will melt the connector. There is a write up and some pics here somewhere that show what happens. Sent a fellow some stuff to repair his a couple months back, along with a relay.

[vzuden]

Also the power wire for the switch at the bike harness has been known to corrode or the connection go bad. Then because of the larg draw will melt the connector. There is a write up and some pics here somewhere that show what happens. Sent a fellow some stuff to repair his a couple months back, along with a relay.

Dion,

Is this writeup you were thinking of?

http://www.venturerider.org/forum/showthread.php?32359-Ignition-Switch-Wiring-Failure

[djh3]

Dion,

Is this writeup you were thinking of?

http://www.venturerider.org/forum/showthread.php?32359-Ignition-Switch-Wiring-Failure

Yup

[cecdoo]

I would be interested in what you find, the 07 trike I just purchased has a very weak sounding horn as well. I planned to install a Stebel as soon as wiring and bracket arrive from Carbon1.

Thanks, Craig

[Midnight]

So I did some checks today to see if I could find where I am getting the 1V voltage drop per my original post causing the stock horns (one on the side and the other behind the fairing) to be weak.

The plug that has burnt up on some members per the post below that leads into the main switch is in good shape and has no voltage loss through it. Plug connection was nice and tight as well.

http://www.venturerider.org/forum/showthread.php?32359-Ignition-Switch-Wiring-Failure

 

So I decided to clean all the connections from the battery on up to the main switch including the connections at the main terminal block. I also dismantled the main switch and checked the insides and all the soldered joints. I had actually drilled out all the break off bolts that hold the main switch together a while back to and replaced them with normal bolts so getting in to check the main key switch was was much easier.

They were all in good shape with no signs of heat buildup or corrosion.

When I put everything back together I was down to just 0.5 volts lost through the system from the battery through the main switch/ horn signal fuse and onto the horn plug itself. I also checked resistance through the same circuits and didn't have any unusual reading. I would think 0.5 volt loss to be acceptable.

 

So I plugged both the horns back in and both still sounded weak. I had already removed both horns earlier and connected them directly to a 12V battery. They were definitely louder when I did that but still sound a bit weak to me.

So I dismantled both horns and checked the internals and they looked to be clean and non corroded as well. When I had them apart I discovered a screw that was glued into position on the back of both the horns that looked to me that if adjusted would increase or decrease the space between the contacts inside the horn. So I adjusted the screw on both horns and low and behold they roared back to life. I will attach a pic at the bottom showing the screw. Its the chrome screw in the attached pic. Now I cant see anyplace in the shop manual that talked about being able to adjust the contacts within in the horns. But I can say for sure that it made quite a difference in the performance.

I have no idea whether they will continue to work well or not or what in all I did made the differnce. Time will tell.

 

PS: Now one thing I forgot to mention in my original thread was I have had a set of RIVCO Air Horns that I installed a number of years ago using a relay that was energized from the horn circuit. The relay in turn energizes the air horn compressor directly from the battery. I had unplugged the air horn compressor from the circuit when I did my checks and whether they are plugged in or not made no difference in the stock horn performance or voltage loss through the circuit. With the stock horns working better than ever and the Air Horns added it is deafening. Exactly what I need when someone isn't paying attention.

Edited November 9, 2015 by Midnight

[Larry1963]

I have recently purchased an 07 and my first thought was the horns are weak, and they have seemed to get weaker. I thought it was just me and I was planning on upgrading to something louder and better.

 

So I ask, where is that screw in the horn? I need to do that to mine too.

 

Thanks for taking the time to post this. It seems that this is a minor problem with these great machines.

[Midnight]

Hi Larry:

I attached a pic in the previous post. Its a screw in the back of the horn body (shiny one in the pic just below the plug in.) With the key on and someone pushing the button adjust it a little bit one way or the other and see if it helps. JR

[Flyinfool]

Once you adjust that screw, don't forget to put something back on it to lock it in place. The vibrations of the horn will quickly change the screw setting if you don't. There is a green loctite thread locker that is made specifically for locking adjustment screws and it is applied to the outside of the tred joint after assembly. The Green bearing retainer is something totally different. You could also try some of the wifes (or your own ) fingernail polish (don't get caught ) to lock the screw after adjustment.