long story - floating needle becomes dead by the side a road

[macmac]

Are you going to tell us what year this is? The more you tell us the faster and better the help you will get.

if not one of these items will stop the bike for good.

Regulator/Rectifier - Rear
Battery Negative Post - (Two wires)
Starter Relay
Radiator Fan
Turn Signal Control Relay
Oil Pressure Warning Light Delay Unit
Joint Connector #1
Regulator/Rectifier - Front
Speed Sensor
Electronic Control Unit (ECU) - (Four wires)
Crank Shaft Sensors
Frame Ground
Fuel Level Sensor
Fuel Reserve Switch
Side Stand Switch
License Plate Light
Tail/Brake Light
Rear Accessory Connection

Yellow Jacket is a ace 12 volt tech. So am I.

If you fry the 2 alternators you won't be happy.

I don't believe this orange connector is the cause. It's just what burned up you found first.

All the black with yellow wires are ground wires.

The list of things these go to Yellow jacket created will stop the bike once and for all.

My bet is the harness dead shorted at the turn down bend against the frame under the gas tank. I can be wrong, but it is a well known fault.

This is the first time on this site I or anyone has seen that connector fry.

Do you know how to remove the gas tank?

[Yellow Jacket]

Junction Connector #1 is gray and is located inside the headlight bucket. It's inside the clear rubber sleeve in the bucket. This is definintely not the melted connector shown in the photos above.

Junction Connector 1.jpg



If the damaged connector is in fact JC #2, I don't see how a short would cause that result. As you know, the very definition of a "short" can not apply to a ground.

However, this could be the result of a poor connection in the JC, which would cause a resistance where there should be no resistance. This would result in heat, which could then cause more resistance, resulting in more heat.

The only ground to the Regulators/Rectifiers goes through JC #1. That means that however much amperage the alternator is putting out, that same amount of amperage is flowing through the ground connections in JC #1. That would be plenty to fry that connector block if it had developed a loose connection (resistance).

I'm beginning to believe that the entire issue with irishguy's bike is a faulty ground connection and not a short circuit.

Will do some more investigating tomorrow.

[macmac]

Really bad grounds can carry a load and fry. That is the sort of thing on cars people think is funny when you turn on most everything and strange things happen like you hear the radio blip in and out with the beeping the horn.

Forcing ground to carry loads backwards.

Yeah a high resistance in that connector maybe could fry it. I have seen that with voltage drops on heaters and AC wiring. The type of damage he stated with white smoke was a high load, and as i see it in the picture it's ground wires that got toasted.

I can't know, but i still suspect a hot wire came in contact with the ground wire at the bend in the harness at the rear of cylinder 2. High resistance don't usually fry in smoke, they melt connectors over time.

[Yellow Jacket]

Originally Posted by irishguy

Think Yellow J is on the money here. Its 2# tucked in below/beside the the battery. Think Wiring runs up under the tank. All black and yellow wires and 1 black with red stripe. Everything visible lights, dash, indicators etc are working, dont know about internals like alternators. Took the plug off the wires were paired one below each other, looks like the far right pair heated and melted together. All the rest where mint.

I'm flying in the dark here so all the help is greatly appreciated

Ian,

Two questions here:

1. What year is your bike?

2. Are you sure about the black with red stripe wire running into that connector?

The reason I ask is because the wiring diagram for the 2005-2008 1600 Nomads shows nothing but black with yellow stripe wires connecting to JC #2. Black with yellow stripe is always a ground.

The only place in the wiring diagram that I can find a black with red stripe wire is in the starter circuit. It comes from the starter button on the handle bar, goes to pin #5 on the ECU and continues on to feed the starter circuit relay located in the junction box (where most of the fuse are located.)

The only other black/red wires I can find are one on the starter lockout switch on the left handlebar (which becomes green/white in the harness) and one on each of the regulator/rectifiers (which become brown in the harness.)

[Yellow Jacket]

P.S. It can be darned difficult diagnosing an electrical problem like this even when you have the bike right there in front of you and have all your test equipment.

What I'm getting at is, it may sound to you like Mac and I have totally different ideas about the cause of your problem. That's really not the case here. We're just looking at it from different viewpoints based on our knowledge and what we have experienced.

Mac has a ton of experience on automotive equipment and has been working on motorcyles way longer than me.

My experience has been partly on Air Force planes, and mostly from 40 years of working on computer equipment, from the old key punch (think punch cards) up to the mainframe computers.

[irishguy]

Yellow, bikes a 2005 1600. Doubled check the color of the wire, its black and yellow with 2 red bands, saw the red and thought it was live, guess it is ground.

You guys know your stuff what do you think my next move is?

thanks

[Yellow Jacket]

OK, first of all, do you have a multi-meter? If you don't then you will need to get one if you plan to try to fix this yourself. You can get a decent meter from Radio Shack for around $25-$30. The digital meters are nearly as cheap as the analog meters now-a-days. You don't need a real expensive one. You may need a soldering iron as well.

What you're going to be checking with the meter is resistance, which is measured in ohms. The setting for that on the meter will be marked Rx1, Rx10, Rx100 and so forth. You will want to use the Rx1 range so that whatever the dial indicates is exactly that in ohms. 1 would be 1 ohm, 10 would be 10 ohms, etc. If you were using Rx10, then 1 would be 10 ohms and 10 would be 100 ohms.

When you measure from each wire in that JC you want to see zero ohms between that wire and a good frame ground.

You just may need to remove every wire from that damaged JC and maybe even replace part of some of the wires, depending on how much of the wire got overheated.

I have seen at least one instance online where the JC had to be completely replaced. It was replaced with a ground strip like you would see in a house hold circuit breaker box. This will look like a square stock bar maybe a quarter inch thickness and several inches long. These will have holes drilled from one side to the other along the length of the bar. There will be a set screw on the top that will screw down into each hole. They are also called grounding bars. The way this works is to slide the end of a wire into the hole and screw down the set screw to hold it in place. You wouldn't need to use one several inches long, probably only about an inch and a half long piece.

Basically, you would remove each wire from the damaged JC, trim the insulation back about 1/4 inch and examine the wire to see if it's burned. It should be stranded copper wire and have a nice copper color. You would want to solder the exposed strands. Then place all of the wires into the holes in the grounding bar (from the same side) and tighten them in place with the set screws. Before you go further, you would want to check the resistance between this new ground bar and a good frame ground. It needs to be zero, or at least 1 ohm or less. At this point you may want to cover the bar and the ends of the wires with a dialetric grease to help prevent future corrosion. Then wrap the entire thing up real good with electrical tape.

If your problem was caused by a degraded connection in the Junction Connecter, which caused high resistance and then heat, this "should" resolve your problem.

It would also be a good idea to check the main harness where it comes down over the rear of the engine as Mac has mentioned. It's not uncommon for the insulation on the harness in that area to get rubbed through causing short circuits.

Please take note, that this is a pretty simplified description so don't hesitate to ask questions.

Click on this link to see an example of the kind of ground bar I'm talking about.

http://www.ebay.com/sch/i.html?_trks...at=0&_from=R40

[macmac]

All the above Yellow Jacket testing shall be done with the battery ground disconnected from the battery, if it isn't now. Otherwise the new ohm meter will blow it's internal fuse.


With this I will back off and read. Maybe add a short note or tip. Too many posters make things confusing.

[irishguy]

Mac, got your directions for removing the tank from another thread if we have to go that direction.

[irishguy]

Yellow/Mac, have a multi-meter on the way, also a grounding bar, instructions seems pretty clear and straight forward, will probably follow up with any questions or issues. thanks to you both for the help

[macmac]

Yellow jacket do you know if there is a Clymers out with a in color wiring diagram now?

I don't know, but if there is it would help irishguy.

irishguy I may owe you an apology too. I have this problem about guys that don't seem to take heed of my warnings, and I am not interested much in well done toasted irish guys, or burned to the ground bikes.

I think you have that idea now, but i didn't know if you did right off fast. You can be a little cryptic and all we can do is guess. Believe it or not we are trying to save your life and maybe some money.

[Boscoe]

Originally Posted by cnc

You got more than a dead battery going on there. Sounds like a short to ground or high resistance in the wiring causing over heating. I think you better have a close look at the harness and connectors looking for damage in the area where you saw the smoke, cause if you ignore it you may fry your harness beyond repair.

High resistance would not cause overheating of the wiring. If the resistance was high, there would be little current flow. When resistance of wiring or connections gets too high, generally lights get dim or things do not work anymore. Too low of resistance (due to a short) is more likely the problem here. You will not "let the smoke out" because of high resistance.

[macmac]

Originally Posted by Boscoe

High resistance would not cause overheating of the wiring. If the resistance was high, there would be little current flow. When resistance of wiring or connections gets too high, generally lights get dim or things do not work anymore. Too low of resistance (due to a short) is more likely the problem here. You will not "let the smoke out" because of high resistance.

yes it would. A High resistance will melt connectors and warp them all bent out of shape, but does not usually make white smoke you can see.

ALL Jap bikes are at risk of toasting stators in the connectors and i have seen many that did fry stators. Hondas Yammi's Susies and ma Kawii all toast stators if the ACV side connectors get a high resistance.

I have also seen this on Dodge cars and trucks Izuzu Troppers on the heater motors, 240 series Volvo heater motors at the connectors always. AC connectors on many other makes, and for so many times i can't keep track.

Feeling the heat by hand is very possible when the circuits are active, Seeing over heated wires is possible cold at the back sides of connectors and you can also measure voltage drop across connectors.

On stator connectors one of the best ways to 'fix' that is to just cut the connectors out and solder the wires. That means to pull the engine from a frame you have to cut the wires, but often times it IS the connector terminals you can not get electrically clean enough no matter what else you do.

Honda recalled stators and at that time the new stator just fried as well. The problem was not stators but the connectors. I saw a lot of mid 80's Gold Wings get stators and i saw a lot of those fry new stators too.

[Yellow Jacket]

Originally Posted by Boscoe

High resistance would not cause overheating of the wiring. If the resistance was high, there would be little current flow. When resistance of wiring or connections gets too high, generally lights get dim or things do not work anymore. Too low of resistance (due to a short) is more likely the problem here. You will not "let the smoke out" because of high resistance.

You are partially correct.

A high resistance in a circuit between the power source and the load will do just what you say above.

A high resistance in the ground path side of a circuit is a different animal.

First of all, it is impossible to short circuit the ground path of any circuit. It is already at ground, how can you "short" it to ground? You can only have a "short" on the power (hot) side of a circuit.

For example, go out to your car or truck. Take a jumper cable and attach one end to the negative (-) post of the battery. Touch the other end of the jumper cable to any metal part in reach and see what happens. Unless you have a vehicle that has the positive (+) post grounded to the frame, absolutely nothing will happen. This is not a short.

Now DON'T do this! ! For example, now take the jumper cable and attach one end to the postive (+) post of the battery. Touch the other end of the jumper cable to any metal part in reach and see what happens. (AGAIN, DON'T ACTUALLY DO THIS - I'M SPEAKING IN A RHETORICAL MANNER HERE.) What will happen is sparks will fly and you may even melt the end of the jumper cable. This is a short.

Now, irishguy's problem is a melted Junction Connector #2. This connector is nothing but a ground bar. There are no wires in this connector other than ground wires.

JC #2 has two wires that go to frame ground. There is also one wire going to the negative post of the battery (through another connector.) All of the other wires basically provide the ground path for every electrical circuit on the bike. To sum it up, nearly all of the power produced by either the battery or the alternators returns to ground through Junction Connector 2. That could be up to 42 amps going through that connector. A 2 ohm resistance in that connector can generate a lot of heat.

Again, you can't short a ground to ground because it is already at ground.

The next thing to understand about the ground path of a circuit is this; High resistance in a ground path is anything over zero ohms.

This is why it's important to keep your gound connections clean and tight.

[Yellow Jacket]

Originally Posted by macmac

Yellow jacket do you know if there is a Clymers out with a in color wiring diagram now?

I'm sorry, I don't know if they do or not.