FIXED: Turn signal problem (left rear indicator not working)

[johnk]

Hi everyone. I have a 2012 Stella 4T, and the left rear indicator is not working.

SYMPTOMS:
—with left turn signal activated, the front indicator stays on steadily, the rear indicator does not turn on at all, and the beep is a steady tone

ATTEMPTED SOLUTIONS:
—changed the bulb
—ensured that the wire inside the cowl is connected to the bulb fixture
—wiped the connector in the front of the cowl (male and female) with a paper towel
—wiggled the bulb a little bit while the turn signal was activated (trying to ensure contact with the ground strap)

FURTHER NOTES:
—I may have made things worse by accidentally loosening the bulb fixture by changing and wiggling the bulb
—the headlight, tail light, brake light, and right indicator are all working normally
—the ground strap in the bulb fixture seems intact, but I don't know how to adjust it or make sure it's snug (as advised here)

I would appreciate any advice you can provide!

[Mr.FixIt]

Electrical checks are a process of elimination.

Get yourself some jumper wires and expose the battery leads.

First test: Is the wiring in the cowl good?
Attach one jumper from the screw that ground screw on the turn signal light to the negative battery post.
Attach the other jumper to the positive lead of the battery post, and touch it to the brassy contact on the front of the cowl. If the light lights then the bulb and holder are good. If it doesn't, the investigate the bulb socket.

The bulb socket has a brassy connector where the wire goes to the front brass contact (which fits into the scooter body). If the connector on the bulb socket center is loose, the connection may be bad there. Touch the positive test lead right to the back of the socket right at the rivet in the center. If that makes it work, then the rivet it loose or corroded. Brush it with a brass or stainless brush. Then mash it down better (gently) with a punch and hammer until it is tight and making a good connection.

Second test if the first test fails:
Move the negative jumper from the bolt to the spring on the cowl where the paint is likely worn off.
Touch the positive lead to the brass contact. This proves the cowl is making contact in both places. If this test fails then there is a bad ground on the bulb socket. If this test passes and the light comes on then the problem is on the bike somewhere.

If the test fails take the screws out of the bulb socket and observe the little tab that goes from the bulb socket to the screw and the connection is clean. Make sure that the connection on the inside of the cowl is clean where the nut goes to ground this bulb socket to the cowl. It may be dirty and may need to be brushed until clean metal is visible. Put some clean grease on it to keep it from rusting in the future. Use a star washer if possible under the nut. The star washer digs into the metal on both sides insuring a good connection. This is likely the problem.

Let us know how you make out and if there are additional troubleshooting steps required.

[Stanza]

If you have a multimeter, check that you are getting power at that front contact on the frame. Positive prong in that contact hole, and negative to something bare metal on the frame. If you are not getting power there (with the turn signal attempting to blink) then you may have a bad positive connection at the frame.

[johnk]

Thank you for these suggestions, Mr. FixIt and Stanza!

I don't have a multimeter, so I started with Mr. FixIt's advice. (I also didn't see the diagram before making this attempt!) No luck yet, but here's what I tried. (I'm going to repeat some of what Mr. FixIt said, to make sure I'm correctly following his advice.) N1 and N2 are the two ends of one test lead; P1 and P2 are the two ends of the other one.

TEST 1 (COWL WIRING):
N1: negative battery post
N2: ground screw on indicator fixture (on the "bulb" side of the fixture, outside of the cowl, with the indicator lens removed, left of where the solid black line is pointing in your diagram)
P1: positive battery post
P2: brass contact on front cowl pin
Result: no light; proceed to test BULB SOCKET

TEST 2 (BULB SOCKET):
N1: negative battery post
N2: ground screw on indicator fixture (same as above)
P1: positive battery post
P2: socket rivet (where the dotted red line is pointing in your diagram)
Result: no light; proceed to test INDICATOR FIXTURE GROUND
Note: there was some sparking and smoking at P2, which I believe was caused by accidentally touching it to another part of the bulb fixture.

TEST 3 (INDICATOR FIXTURE GROUND):
N1: negative battery post
N2: cowl spring
P1: positive battery post
P2: brass contact on front cowl pin
Result: no light; proceed to work on indicator fixture ground.

I tried my best to follow your directions here. (I have no clue what I'm doing, so if any of what I'm saying doesn't make sense, I welcome corrections.) I removed the whole indicator fixture from the cowl by undoing the two nuts on the inside of the cowl. Both of those already had star washers under them. I sprayed electronic cleaner on the tab/band thing that touches the side of the bulb fixture and on the screw that holds it into the fixture (all around where the solid black line is pointing in your diagram). I brushed the inside of the cowl where the ground screw goes, down to bare metal. I applied some dielectric grease there and screwed everything back together. For good measure, I also sprayed electronic cleaner in the bulb socket, in the front cowl pin hole, and on the rivet on the back of the bulb socket. Still no light.

I would love to hear what I might have done wrong, or what else I can do. Thank you again for all of this information, as well as for your patience.

PS. I am interested in eventually upgrading to LED indicators and a new solid-state LED flasher (following this post). If that might circumvent this problem, I would be happy to try it. But I won't get my hopes up, because it looks like the issue has more to do with the components that won't be changed as part of that upgrade.

[Mr.FixIt]

johnk,

Does the bulb light?

Take the bulb out of the socket. While connected to the battery... Touch the black wire to the outside and the center pin to the red wire. It should light up, or the bulb is bad.

One final test (which probably should have been the first test). Is the socket any good.

TEST 4 (Is the socket good):
N1: negative battery post
N2: Socket strap
P1: positive battery post
P2: center pin of the socket

If this one fails, the socket must be bad in some way. Is there dirt in it? Is the rivet that holds the center pin so corroded that it won't conduct?

I've got a little video to share
https://youtu.be/qMD30Osi_qg

[johnk]

I'm pretty confident now that the bulb is good and the socket is bad. (I will double-check according to your instructions in the morning.) I haven't seen any dirt or corrosion.

I just bought the scooter "new" (6 years old but unused) from a dealer, so it has been sitting for a while, but it doesn't have much wear and tear. The indicator wasn't working when I bought it, but unfortunately I didn't notice that until I got it home, and it would require a rental truck to get it back to the dealer.

Changing the bulb was the first thing I tried, but I didn't do it gracefully. The socket is definitely not snug in the fixture anymore. So maybe the original bulb was burned out and I messed up the socket trying to replace the bulb.

Thanks again!

[johnk]

This video is immensely helpful!

I tried touching N2 and P2 directly to the bulb, and it did light up, so the bulb itself is good.

I tried the test at 3:55 in your video, and the bulb did not light. (Same with touching one lead to the strap.) Since the bulb is good, it seems clear that the socket is the culprit.

At 9:46, you say the clip on the back of the fixture shouldn't move. Mine does move, and the socket itself rotates about 180º in the lens side of fixture.

So the part of the circuit between the rivet and the center pin in the socket seems to be where I'm losing current. I tried gently hammering the rivet with a small screwdriver as a makeshift punch to no avail. As far as I can tell, hammering the rivet isn't making the fixture hold on tighter to the socket. (But maybe some more careful punching, or soldering, would do it.) Beyond that, it's not clear to me how I can manipulate the socket at all from the lens side of the fixture.

Thank you again—all of your help has taken me from 100% clueless to near-certain about the locus of the problem.

[johnk]

Hi Stanza. My new multimeter confirms that the front cowl pin is getting power. Thank you for the suggestion!

I ordered a turn signal fixture from eBay, so I'll give a status update when it arrives.

[johnk]

Okay, now I'm even more confused!

I got a replacement turn signal fixture from eBay, parted out from a 2005 Stella. First I tested the fixture to see if it works (one test lead on the ground strap and one test lead on the rivet), and it does. I installed it into the cowl. I tested the cowl wiring (one test lead on the ground strap and one test lead on the front cowl pin), and it works too. But then I put the cowl back on the bike, and the original problem returned—the bulb doesn't come on at all!

I double-checked the fixture and cowl wiring again, and they're fine. Figuring I had nothing to lose, I went ahead and replaced the stock flasher box with a CF12ANL-01 LED flasher (again, following this post). (I don't have LED bulbs yet, so I'm still on the stock bulbs.)

This did not fix the problem—with the left turn signal on, the rear indicator still doesn't come on at all. However, the front indicator now flashes, as opposed to staying solid, as it did with the stock flasher box. The right turn signal continues to work fine.

This situation is perplexing because there appear to be two independent causes of the same problem—the old fixture was broken, but even a working fixture doesn't work! Where else on the bike might this problem be coming from?

[VSP]

Have you charged the battery? The blinkers and flasher relay will do odd things (like you described) when the battery is low.

[Mr.FixIt]

I've noticed the same thing about the turn signals. Mine required a good battery charge in order to work properly.

Stick the voltmeter in the socket on the side of the bike where the pin fits in. It should indicate voltage when trying to use that side turn signal.

[Stanza]

It's also possible that the socket on the bike (pin hole where it gets power, that you tested earlier) is working, and the wiring in your cowl is working, but for some reason the cowl is not contacting the power source on the body. Have you tried supplying power directly to the pin on the sidecover? Or only to the bulb socket?

[johnk]

Thank you for the suggestions, VSP, Mr. FixIt, and Stanza!

The multimeter directly on the battery reads about 12.2. A little Googling tells me it should be closer to 12.6. Might that be the problem?

With the positive multimeter lead in the front cowl pin socket and the negative lead on the frame and the turn signal switched on, it reads about 7.6 and 1.3, flashing back and forth. (Recall that I have the LED flasher relay installed, in case that's relevant.)

Stanza—you may be right that the front cowl pin isn't making contact with the body. The bulb does illuminate with one test lead on the ground strap/ground screws and the other on the front cowl pin. I sprayed the pin and socket with electrical cleaner and added some dielectric grease, but that didn't make a difference.

I have a Battery Tender Jr. arriving in the mail tomorrow. Thanks, everybody, for working through this with me!

[Stanza]

7.6 is way too low, it should be in the 11 to 12 range at minimum. With the turn signal flashing, can you take a reading off the front turn signal? See if it's at a similar voltage. If it's not, then you have a wiring problem for the rear turn signal specifically. If I remember correctly, there is a wiring diagram for this bike in the service manual.

Manuals can be found here:
http://www.modernbuddy.com/forum/topic17349.html

[Mr.FixIt]

The standard DC multimeter has filtering in it. So don't trust it to give an accurate reading on a pulsing DC voltage. A test lamp to draw current or analog meter is more useful in this instance to make a good determination.

If it really isn't reaching the full voltage however, then that means there's a poor high-resistance connection somewhere producing a voltage drop.

[johnk]

I ran a test today that I can't believe I didn't try earlier: one test lead connecting the negative battery post to a ground screw in the cowl, and one test lead connecting the front cowl pin to the socket it goes into. And the turn signal worked!

So the problem appears to be that the front cowl pin isn't going all the way into the frame when the cowl is attached. In fact, you can see a pretty significant gap in the attached photo.

If I can get the cowl to fit flush to the frame, I think the problem will be fixed. Any advice?

My hypothesis about this whole ordeal is that the cowl pin has been the real problem the whole time, but I broke the bulb fixture when I initially tried changing the bulb, creating a huge red herring. That would explain the two independent causes of the same problem.

[Stanza]

Take a look at the section of the sidecover that the retaining latch tugs on to hold it against the bike. Is it bowed out? If so, take a mallot and tap it back a bit. That should make the retaining latch pull the cowl more snugly against the frame.

[johnk]

Here's a photo of that segment, before applying the mallet. It doesn't look bowed, but you can see that the cowl wire has popped out of the little clips that are supposed to hold it to the edge, which might be a sign that it's bent. I gave the latch several whacks with a mallet in the direction that would pull it closer to the frame—downwards in the attached photo. It seemed to bend slightly, but it's still not making contact. Should I keep whacking? (I'm afraid of causing permanent damage!)

In the photo attached to my previous post, you can see that the cowl bends outward near the cowl pin and the frame bends inward. Does that look normal?

[johnk]

Another possible solution that wouldn't require any cowl modification is to insert a spring or screw into the cowl pin socket to complete the circuit. Do you think that could be done safely without causing any damage?

EDIT: I just spoke to a scooter mechanic who said it would be a very bad idea to stick any foreign objects in the cowl pin socket.

[johnk]

I asked a motorcycle mechanic about this problem, and he recommended putting a ball bearing in the cowl socket. I went to my local bicycle shop and bought a few different sizes. I squirted some dielectric grease in the cowl socket, and the first ball bearing I tried fit perfectly. I think it was 5/16''.

Problem solved!

Despite the aforementioned scooter mechanic's advice against inserting foreign objects, the only other solution I could think of would be to either try to reshape or replace the cowl. The motorcycle mechanic was confident that the ball bearing wouldn't cause any problems.

Thanks again for your enormous help, everyone!

[Mr.FixIt]

Sometimes we do what works. Glad to see it is operational.