Turn signal running light problem

When I purchased my Silverwing about a month ago, I purchased it with a known electrical problem. So now it's time to tackle the problem.
First off the left turn indicator on the dash is glowing bright all the time. Second, the running light on the right side rear doesn't work however the turn signal itself is working. In fact all turn signals work. It's just that the right running lamp doesn't. Being a circuit with a dual purpose and a single element lamp, some investigation is required as to the actual circuit. In my testing so far I have found a lot of dirt in the turn signal switch so I disassembled and cleaned it then checked for complete continuity. I found no abnormal resistance in the switching. Readings were less then .01 ohms so we know the wiring and contacts are good. After cleaning and a touch of electrical grease, the switch functions with ease. Next I checked the wiring between the rear of the Silverwing and the connector at the dash. Again no abnormal readings or high resistance problems. Injecting 6 to 10 volts into the wire, the lamp properly glows. That leaves me only 3 other things to check. Either a diode is malfunctioning on the dash circuit board or it's in the on board flasher unit itself. Or there is possible a faulty trace on the circuit board. While I'm in there I was going to look at possibly slowing down the flasher unit by adding a resistor to produce a false load so LEDs can be installed in the circuit. It should't be a problem to recalculate the flash rate to find an acceptable range of resistance to load the flasher.
Has anyone else had this issue?

I'll keep everyone posted.

Today I was looking through EBay just to see what Silverwing parts were available. I found a claimed working dash display for $24 US and a turn signal switch for another $12 US. Both with free shipping so I purchased them. Just out of curiosity my plan is to plug in the new dash display and check its reaction to my problem. If all goes well, that will be it. I will also compare and troubleshoot the components to find what actually went wrong. It should be a good learning lesson into Honda designs.
If I do the board swap and it works out well, I wonder how and where the mileage memory is kept and can it be updated to reflect the true mileage of the Silverwing. I'm assuming at this point that the memory chip probably an eprom type chip on the dash pcb board.
Lot of curiosity here.

If there is a significant difference in mileage and the new is less you may have to claim that at resale, it may be the case either way, check o-HI-o / federal law to CYA. Honda takes delight in shared circuitry have fun

Not sure yet. I wont get the new dash pcb until next week. The bike scrap yard didnt have a milage on the unit when it came in for recycle. They just parted out what was still good.

Ken j wrote:

Not sure yet. I wont get the new dash pcb until next week. The bike scrap yard didnt have a milage on the unit when it came in for recycle. They just parted out what was still good.

Curious was this an in state company or out of state.

It was purchased out of Colorado. From, my understanding mileage does not need to be presented when purchasing a used part. For that matter I'm not even sure where the mileage is digitally recorded on the Silverwing. In a car, the mileage is not tracked in the ECU but rather recorded on a chip in the dash display so I'm assuming it's the same on the Silverwing. Once I power up the new (used) display, I'm assuming I will see the mileage of the bike it was taken from. If it is less then I would say 500 miles, I think I would leave it as is. However if more then 500 miles, I think the state needs to know and direct me at the title bureau on how to proceed. About the only thing I use an odometer for is preventive maintenance. I run vehicles with over a quarter million miles on them all because I'm a stickler for proper PMs.

I'm also not shy about removing parts from a PCB and replacing them. I've repaired hundreds of boards in my time. Nothing a proper soldering iron and solder can't handle.

Please let us know how you get on with your new display board and locating the odometer chip.

Thanks, I'll follow your adventure with this replacement.
Maintenance comments have been made on my writing on my equipment, a Plano china marker is a handy thing, open a hood or look at a filer and you will see the next maint. interval or the date something was last changed, quick EZ and no looking for a record book although you would find one in the glove compartment.

Cosmic_Jumper wrote:

Please let us know how you get on with your new display board and locating the odometer chip.

I would be more then happy to. Anything I can share to help others maintain their Silverwings, I will post. Going to head out in a bit and take a few pictures of the problem so everyone can see. We can do a start to finish sort of thing.

Here is the problem as displayed.
Left turn signal indicator glows all the time except when left turn signal is activated. Then blinks normally.
Front running lights work.
Rear right running light does not function but blinks normally when right turn signal is activated.
Turn signal switch has been cleaned and functions normally. Switch was checked electrically and functions correctly.
Wire harness from dash connector back to rear right signal was tested and no issues found.
Conclusion: The problem is up in the dash display board. Possibly a bad diode not allowing current to correctly flow.

When the new (used) display comes in I will continue. My thinking tells me that we should go over the entire board naming components and their functions. I use to teach this stuff before I retired as a college teacher so it's no big deal for me to share this with everyone.

Just a suggestion Ken. Take your FSM down to your local print shop and have a 2’ x 3’ print made of the wiring diagram for your model (ABS / non-ABS). It makes tracing circuits soo much easier.

I have the manual and can print out a blowup of the wire diagram. Just a matter of scanning it and sending it to the plotter at the college.

I got the new dash panel in on Monday. Talk about fast shipping. It's just like the pictures on EBay shown and the scrap yard did say it worked so I went out to the garage and removed the covers to access the connectors and plugged the new board in. Low and behold the new board started right up except I still had the same problem as with the old board. Left turn signal indicator glowed, right rear running lamp not working, turn signals worked just fine. Time to scratch my head here with a WT? look on my face. Now I'm thinking that it is not the board and not the turn signal switch. I'm now thinking something in the wire harness. So I started looking down the cover opening and I find the connector for the front turn signals and headlights in the front tupperware. I noticed the wire was taped in a bundle and not in the plastic tube. I disconnected the connector and turned the key to the on position. Obviously no front lights but the left turn signal indicator stopped glowing. Could I have a short circuit in the front clip wire harness? I let it go until today when I got home from work.
More in next post.

Today when I opened the front clip a bit to get better access to all the wiring, I found that the previous owner or one of his buddies ( a professional mechanic wouldn't do this) did some bogus chopping of the front clip wire harness and splice in a wire between the front left turn signal wire at the lamp and the left rear turn signal wire at the dash panel connector effectively bypassing the left turn signal diode on the board. Another WT? goes off in my mind and I cut the booger out. Now there is no rear running light and the left front lamp glows on running but no left front turn signal. However the left turn signal dash indicator in now off. Mind you I did this testing with the original dash board in the Silverwing. Upon installing the new (used) board as a test, the front turn signal worked just fine. In fact all turn signals worked and I had front running lights but no rear running lights. Now we are getting somewhere. At this point I noticed something and my mind started thinking. Feel the gears grind and the smoke pouring out of my head so to speak. I started looking at  mine and my wife's cars. I noticed that both did not have amber running lights on the rear of both cars. Then I went out in front of the house and looked on the street at the parked cars. Not a single car had amber running lights on the back of the cars and all the rear side markers were red, not amber. Then the question??????  Do Honda Silverwings have rear amber running lights at all????  So I went on You Tube and searched for Silverwing videos. Looking at several videos I noticed that none of the Silverwings in the videos had glowing amber rear lights while the bike was moving down the road. I assumed a Silverwing had rear amber running lights because my left rear turn signal light stayed on and assumed the right one didn't work thinking a problem where in fact the only problem is the left front turn signal not working.

Final conclusion for the evening? I actually have a front left turn signal failure in the dash board. Now I can get to the bottom of it. Time to remove the existing dash and compare components between the two dash boards. Because the previous owner put that booger jumper in, I can safely assume it was a quick quack fix to solve his problem so he would not have the expense of buying a new dash board and have turn signals.
Nice try booger guy. Maybe that's why you sold me the Silverwing for only $1000 thinking you dumped a major problem on someone else to worry about. I got your number and the knowledge to fix it right for just a few dollars.

On a side note, the dash panel direct from Honda parts is $850 new. Maybe that's why the previous owner did what he did and put the Silverwing up for sale cheap. His lack of understanding is my gain. I'm really loving my Silverwing now. LoL!!!

My Swing doesn't have rear running lights, so at least you solved one piece of the puzzle!

I'll admit to being an electrical noob but it looks to me like the function of running/turn light is controlled through the diodes and transistor circled. I'm assuming current can run one way to just the running lights, or in the other direction and blinking to a single side at a time. Orange and blue wires are for the respective sides, with a solid going to the rear lights or with a white stripe to the front lights.

Hopefully there is a more clued-up electrical expert on the forum to guide you (and me) further.

Soooo....

My reading of this is that by default the transistor feeds 5V power from the dash into the blue-black wire, that heads to the left switch pod and splits back into the orange/white and blue/white wires and powers the marker lights. A diode stops the current reaching back to the dash light.

When you activate the indicator, it completes the circuit Bl/Lg to the flasher unit then grey to the switch pod then back down the orange or blue wire which splits to the back indicator and forward to a split which powers the dash light and front blinker.

If your dash light is on with the marker light, then the diode specific to that side must have failed.

Anyone who can explain the circuit-ry workings with that clarity sure ain’t a Noob. Thanks Terry.

I totally agree. Terry knows more then he thinks. That explanation was spot on how the circuit works. Thanks Terry.

However there is more to the circuit then the wire diagram shows. That additional circuitry is on the dash PCB itself. There should be two ballast resistors soaking up the lamp load regulating the flash rate depending upon lamp wattage. The higher the wattage, the slower the flash rate. That's why LEDs flash so fast when you install them. Not enough load because the ballast resistors cant soak enough of the load increasing the flash rate. I'll be getting into the physical PCB boards later this week.

Here’s a look at the front (front of bike) side of that Combination meter. I assume that D507 & D506 are the diodes Terry circled. And that RY701 is the Turn Signal Flasher with R709 & R791 the load resistors.

If that be the case then it’s possible that those components could be replaced in situ.




And the rear of the Combination Meter board (facing rider):


Can anyone identify the transistor Terry circled?

Terry's transistor. Third pic (front side) right under the RPM indicator because it's right in line with the backside of the ballast resistors. Hard to see in the pic.
Then again that trans may also be the driver for the tach because there is one somewhat in the same position near the MPH meter. Hard to tell without physically tracing the board. I'll know more when I get home and start tracking and testing my new (used) board.

One thing I did notice about the new board was the RPM reading was 1500 at idle where my original tach showed about 950 at idle so it appears the new board may be out of calibration on the tach and mph meters. There should be calibration pots somewhere on the board. If not, we can do it old style and adjust the needles vs the spring load return tension on the movements tweaking them in.

I believe the 1500 RPM figure to be more accurate than the 900 RPM figure.  At least that is what mine idles at (1500 RPM).

Mine runs about 1450 at cold start then comes down to 950 after warming. I have a hand held tach for troubleshooting and my current tack on the Silverwing matches my handheld. I still have a lot of tweaking to do since I only owned the Silverwing for about a month now. Still haven't gotten into the belt and clutch yet. After finding that booger jumper in the front clip, my thinking is going to removing all the Tupperware, cleaning it inside and out and see what other boogers the previous owner left me. All in due time.

I suspect the needle-repositioning is the easy way to calibrate the tacho. I've seen a video where the dash was being rebuilt and the needles were carefully lifted over their stops to allow them to rest fully, and that position was marked on the dash with a piece of tape so they could be put back in the same orientation.

Idle speed adjusting is as easy as accessing the screw between the throttle bodies; if you know what you are feeling for it can be done with the maintenance cover in place, through the access hole.

Turns out I had another spot of good luck. The left turn signal diode wasn't bad or burnt out. It was missing and never soldered in the board properly. When I took the dash out of the Silverwing, I noticed a noise from inside the case. Like something was in there rolling around. I took the case into my kitchen where I have great light and disassembled the case exposing the board. Sure enough a diode fell out on the table,. I examined the board and found the diode missing from the board Maybe it was just tacked in at the factory and slipped during wave soldering the board. Over the years the vibration must have caused it to let go falling into the case and causing the problem. I cleaned the holes and soldered the diode back in. Cleaned the clear plastic and tested the unit on the Silverwing. Problem solved and now it's a matter of putting things back together.

Before I close up my Silverwing, I'm going to try out a modification. The previous owners booger jumper gave me an idea. I believe I may be able to modify the rear turn signals to be marker lights as well as turn signals using a jumper wire for each side. The modification must be made at the connector going into the dash board. That's the easiest place to do it where all wires are present.

Step one: Remove the orange (O) and light blue (Lb) wires from the connector. They must be fully disconnected from the anode side of the diodes so they must be cut or the ends removed from the connector. I suggest taking a micro screwdriver (glasses screwdriver) and remove them from the connector and tape off the ends with electrical tape. If you don't like the mod and cut the wires, you have to resplice them. If you remove the f-pins from the connector and tape them and don't like the mod, simply put them back.

Step two: Splice the orange and orange/white wires together using a fold over wire connector.

Step three: Splice the Light blue and light blue/white wires together using a fold over wire connector.

That should give you rear marker (running ) lights and turn signals in the rear of the Silverwing.

Removed wires are in white or blanked out and new tap is in red on the wire diagram.

Please do not try this until I report back and let you know if the mod will actually work.

oldwingguy wrote:

 the Columbo of electronics and good luck.

It's us oHIo guys using the S.W.A.G method of electrical engineering.
SWAG= Scientific Wild Azz Guess. LoL!!!

That's excellent work Ken!

Ken j wrote:

oldwingguy wrote:

 the Columbo of electronics and good luck.

It's us oHIo guys using the S.W.A.G method of electrical engineering.
SWAG= Scientific Wild Azz Guess. LoL!!!

Just be careful and don't let the smoke out

Hold off on the idea of rear marker lights for now. I gotta do more research into the idea before formally presenting it. There is more to it then a few wire taps.

Ken j wrote:

Hold off on the idea of rear marker lights for now. I gotta do more research into the idea before formally presenting it. There is more to it then a few wire taps. 

FYI Only the 2002-2007 wiring diagram for the Combination Meter shows those diodes and transistor (on both ABS and non ABS models).

After 2007 models (ABS & non ABS) do not show the transistor or diodes.

If you do have luck in moding the CM wiring to allow the rear turn signal to function as running lights I hope that you can figure out how to sort later model wiring for that as well.

The rear turn signals branch off on the upstream side of the diode; you need to move their power supply to the downstream side of the diode I think. If you just join across the existing wires you will be feeding the marker light power back to the indicator lights in the dash.

Easiest would be to pull the solid orange and solid light blue connectors out of the multiplug at the dash, and join these to the light blue/white or orange/white wires.

Terry Smith wrote:

The rear turn signals branch off on the upstream side of the diode; you need to move their power supply to the downstream side of the diode I think. If you just join across the existing wires you will be feeding the marker light power back to the indicator lights in the dash.

Easiest would be to pull the solid orange and solid light blue connectors out of the multiplug at the dash, and join these to the light blue/white or orange/white wires.

That is exactly how I described the procedure I was going to do and the results did not achieve our goal. The idea was to parallel the front and rear lights. (see my diagram a few posts above) There is something more to it. The orange and lt blue wires also go to the turn signal selector switch. To get the indicators to work power must come from that switch. If you parallel the front and rear and remove power from the anode side of the diode, the indicators no longer work.

Can we achieve rear amber marker lights? Yes. However to just parallel the front and rear removing those wires from the anode side of the diode, we sacrifice the turn indicators on the dash. For me, not an acceptable trade off.

It looks like the break point of the orange and lt blue wires will need to be after the switch tap points, then paralleled with the front lights. It's going to involve a little more then I planned to find the tap points. I'll keep working on it.

This is what I'm seeing in the 2002 service manual diagram.