Turn signal issues...I don't know what's going on...

[DRWfan1926]

So here's my conundrum...

The other night, after changing my brake pads, my neighbor noticed that my brake light is out.  Being the good neighbor he is, he gives me one of his 1157 bulbs to replace it.  Put it in, and all is good.  A couple of days later, I find that my turn signals, brake light and horn all don't work.  I figure that it's a blown fuse, so I check the 10A fuse and, sure enough, it's blown.  I replace the fuse, and all is good...until I hit the left turn signals, and then nothing works again.  I recheck the fuse, and it's blown again.  Feeling brave (or stupid) I replace the 10A fuse with a 15A to hopefully see what's going on before the fuse blows...and it worked.  When I start the bike, everything is working/lit as it should be.  Horn...check.  Headlight high and low beams...check.  Tail light and brake light...check.  Right turn signals...check.  Left turn signals...Houston, we have a problem.  When the left turn signal is engaged, the front flashes faintly, as does the turn signal indicator light.  The rear turn signal doesn't light up/flash at all. Additionally, the headlight, tail light and any other indicator lights that may be on (i.e., high beam, neutral) all dim and brighten in time with the flashing turn signal.

I thought it might be the relay, but after reading about some similar issues on the forums, now I'm not sure.  I didn't see any topic that is exactly like what I'm experiencing, but if its there and I missed it, I apologize for the duplicate thread.

I definitely need assistance from those who are much smarter than me.

Thanks in advance.

Craig

[Hook#3287]

Don't know about the smarter thing, but it sounds like it could be a short or ground issue.

I would check the wiring connection under the rear fender.

If alls good there, just follow the wires back looking for abnormalities.

Interstate, standard or tourer?

[DRWfan1926]

Thanks, I'll check it as soon as I can.

And sorry...I have a 2000 standard.

[Chrisj CMA]

Change the left side blinker bulbs, remember the front one is double filament.

[rhinor61]

The fuse is To protect the circuit/wire from catching on fire and burning your bike to the ground.

Two ways you can blow a fuse:
It will BLOW when the current exceeds the fuse load rating.
2nd it will BLOW if the protected circuit bare wire touches metal/ground, a direct short.

I have seen corrosion in bulb sockets that can create a path from the positive contact to ground.
Which will blow a fuse.

A 12vdc test light (not self-powered) is a good tool to have, Harbor freight has them for $6-10.
you don't need a fancy digital multimeter for most 12vdc troubleshooting.

John

[DRWfan1926]

Thanks everyone.

I've checked the left rear turn signal contacts, and I didn't find any corrosion.  I've also swapped the bulbs between the left and right sides, but it still does the same thing on the left, and the right works just fine.

Hopefully I will have some free time tomorrow to do a little more digging.

[Itinifni]

Sounds like you have a high resistance short to ground in the power circuit to the left, rear directional. Possibly a wire with the insulation abraded off and a bit of corrosion to the bare wire to add resistance.

We know that it's drawing over 10 amps because you blow a 10A fuse, also know it's drawing less than 15A because that fuse doesn't blow (well it could be 15A or a little more but I won't go into that here). When you have the 15A fuse in the front directional flashes dim because you're shunting most of the available current to the short, the remaining lights dim when the directional is energized because you're adding a 10-15A load to the system.
I wouldn't advise leaving the left directional on with the 15A fuse for any length of time as you're generating a lot of heat in the harness flowing that much current.

I'd get a few spare, 10 fuses and install one, then remove the left, rear turn signal bulb and turn on the directional. I know you've swapped bulbs side to side but sometime the short is in the socket. When the bulb is out to contact moves forward a bit and may open the short. If the fuse doesn't blow with the bulb out take a hard look at the socket, you may have to disassemble the lamp for a thorough inspection.

If the fuse still blows remove the rear plate/turn signal assembly from the rear fender to access the wiring to the directionals. You may get lucky and see an abraded wire. If not unplug the bullet connector for the source wire to the left directional. You'll have two wires coming out of the directional to the harness, one will go into a double bullet connector (that's the ground and I believe it's Green), the other will go into a single bullet connector (that's power, I think Orange). With the power wire unplugged and a fresh fuse in try again, if the fuse doesn't blow the short is in the orange wire or the socket.

If the fuse still blows move up the circuit to the next connector. I believe the rear fender sub-harness connector is either under the seat or under the taillight. When you find it just unplug the whole connector and try the directional again. Fuse doesn't blow now, the short is in the sub harness between the connector you just removed and the orange bullet connector you unplugged in the previous step.

If the fuse still blows the short is in the main harness, look for any signs of abrasion against the frame. I suppose it's also possible there could be a short right at the directional switch but that's unlikely, I think you're going to find it in the rear fender sub-harness or directional lamp itself.

Good luck,
Matt

[Cracker Jack]

Sounds like you have a high resistance short to ground in the power circuit to the left, rear directional. Possibly a wire with the insulation abraded off and a bit of corrosion to the bare wire to add resistance.

We know that it's drawing over 10 amps because you blow a 10A fuse, also know it's drawing less than 15A because that fuse doesn't blow (well it could be 15A or a little more but I won't go into that here). When you have the 15A fuse in the front directional flashes dim because you're shunting most of the available current to the short, the remaining lights dim when the directional is energized because you're adding a 10-15A load to the system.
I wouldn't advise leaving the left directional on with the 15A fuse for any length of time as you're generating a lot of heat in the harness flowing that much current.

I'd get a few spare, 10 fuses and install one, then remove the left, rear turn signal bulb and turn on the directional. I know you've swapped bulbs side to side but sometime the short is in the socket. When the bulb is out to contact moves forward a bit and may open the short. If the fuse doesn't blow with the bulb out take a hard look at the socket, you may have to disassemble the lamp for a thorough inspection.

If the fuse still blows remove the rear plate/turn signal assembly from the rear fender to access the wiring to the directionals. You may get lucky and see an abraded wire. If not unplug the bullet connector for the source wire to the left directional. You'll have two wires coming out of the directional to the harness, one will go into a double bullet connector (that's the ground and I believe it's Green), the other will go into a single bullet connector (that's power, I think Orange). With the power wire unplugged and a fresh fuse in try again, if the fuse doesn't blow the short is in the orange wire or the socket.

If the fuse still blows move up the circuit to the next connector. I believe the rear fender sub-harness connector is either under the seat or under the taillight. When you find it just unplug the whole connector and try the directional again. Fuse doesn't blow now, the short is in the sub harness between the connector you just removed and the orange bullet connector you unplugged in the previous step.

If the fuse still blows the short is in the main harness, look for any signs of abrasion against the frame. I suppose it's also possible there could be a short right at the directional switch but that's unlikely, I think you're going to find it in the rear fender sub-harness or directional lamp itself.

Good luck,
Matt

What is a "high resistance short to ground"? Never heard that phrase before. How is that different from a regular "short to ground".

[Itinifni]

Short to ground is the usual type of short circuit i.e. bare wire against the engine block, frame etc. Blows fuses right away pretty much regardless of what amperage fuse you use, the exception being if you use a fuse that can safely carry more current than the wire in which case it's the wire that eventually opens (melts) resulting in smoke and lots of damage.

In a high resistance short to ground (or to power or to another circuit) there is some resistance between the circuit and ground (or power or unintended circuit), usually in the form of corrosion. The most common time I see it is in connectors that are exposed to the elements. If you get a bit of corrosion between adjacent pins you can start to build up continuity between them. The more corrosion the less resistance.
As the resistance decreases you effectively have two, parallel loads on the circuit (or in this case four counting the front directional and indicator. Eventually the load becomes enough to blow the fuse.

I've seen this type of short a fair number of times in door harnesses.

[DRWfan1926]

Sorry for not checking back sooner, but I hurt my back earlier in the week and today I was finally able to get out and do some more inspection on the bike.  Here's what I found...

I removed the tail light/turn signal assembly and pulled the wires out.  On the orange wire, there was an oh so small cut.  With the assembly out, and the wire not touching anything, the turn signals, brake and horn all worked perfectly.  I fixed the wire, covered the repair with shrink wrap, and buttoned everything back up...and all is as it should be.  And if anyone is wondering, yes, I put the 10A fuse back in.

Thanks for all the help.

[DRWfan1926]

Sounds like you have a high resistance short to ground in the power circuit to the left, rear directional. Possibly a wire with the insulation abraded off and a bit of corrosion to the bare wire to add resistance.

You are correct...

[Itinifni]

Easy, cheap fix, wish they were all like that!

[Wewaman]

Hey Itinifni,
  thanks for the electrical lesson 

VERY informative,
  Tony

[MarkT]

Sorry for not checking back sooner, but I hurt my back earlier in the week and today I was finally able to get out and do some more inspection on the bike.  Here's what I found...

I removed the tail light/turn signal assembly and pulled the wires out.  On the orange wire, there was an oh so small cut.  With the assembly out, and the wire not touching anything, the turn signals, brake and horn all worked perfectly.  I fixed the wire, covered the repair with shrink wrap, and buttoned everything back up...and all is as it should be.  And if anyone is wondering, yes, I put the 10A fuse back in.

Thanks for all the help.

Did you find the sharp edge that made the cut, and dull it?

[DRWfan1926]

Easy, cheap fix, wish they were all like that!

Amen!

[DRWfan1926]

Did you find the sharp edge that made the cut, and dull it?

DOH!!!   

Honestly, I didn't notice any sharp edge.  The wires were tucked into the tail light housing, and the only thing that I can say I remember are the edges of the connectors.  I'll put it apart again and get a better look.