Small electrical/light issue

[armyofda12mnkeys]

Hello all,
I was debugging a electric start issue and think I had some bad connectors on starter relay and battery so i fixed those and now moved onto this...

My right right turn signals always seem dimmer than my left ones. Realized today when i turn the right signals on, the left signals are slighttttly on too, so i guess some voltage/electricity is leaking here when it shouldnt. I learned a little bit about Voltage Drop testing so did a bit of that (on the back signals at least) below...

When I turn the left signals on, the left back turn signal light has >10V going to it (don't have a super accurate Voltmeter, just an analog one right now so its about 10-12V) and
0V going to the right.
When I turn the right signals on, the right back turn signal light has >10V going to it and 5V going to the left.

What could be the issue? I guess I learned how to do Voltage Drop testing, but how to actually fix an issue like this.
I had new turn signals put on the bike, but don't think that could be the issue, since mechanic probably spliced the old lights off and put wire for new lights in.
Here is the issue in video form if it helps understand whats going on...

Thanks!
Ari

 

[16VGTIDave]

I'd be checking ground wires first, then the switch. If that doesn't resolve the problem, you can also try isolating it by disconnecting one light at a time and checking the system. It might me a pinched wiring harness with wires shorting.

HTH,
Dave

 

[jmd_forest]

If you trace thru the wiring diagram you will see that the turn signal circuit backfeeds the instrument bulb ground thru the opposite side blinkers. The opposite side blinkers will light if there is too much current in the instrument bulb circuit because the current from the intended side blinker bulbs is being diverted thru the instrument bulb due to the intended side blinkers being poorly grounded. Clean the grounds and clean the bulb sockets. A pinched wire would more likely result in a blown fuse.

 

[armyofda12mnkeys]

jmd_forest (Jeff) helped me out in a private message to figure out the problem...
I had after-market turn signals and the bulbs were the problem:

Jeff:

With the new info regarding the aftermarket signals I am pretty sure the problem is with the bulbs. I doubt anything you did regarding the electronic ignition is causing the problem. Also, not knowing what types of bulbs and sockets are in your new signals I don't know if you can replace them with factory equivilant bulbs. Replacement the bulbs with factory equivilants, if possible, would be the easiest fix. The bulbe in your new usit probably have higher internal resistance than factory bulbs and that causes more current to backfeed thru the indicator bulb and light the opposite side.

Me:

Hey Jeff,
I was testing again last night after cleaning some connections, noticed the problem happens on both sides.
and ... You are right!, I put in the old turn signals (the rear ones, at least). and the 'other side lighting up' problem goes away!
The back part of the stock turn signal says what bulb to buy I think: 12V32CP (27W) or 6V21CP(17W) [although it also says 21W for some reason at the top as well], pic of stock signal with specs:
http://farm9.staticflickr.com/8479/8...1185c6e6_b.jpg
The stock bulb inside the stock housing itself says 12V32CP on it...

My new turn signal light bulb just says 12v10w.
They are much smaller bulb than the stock bulb hehe.
Wonder where I can find a possible equivilent sizewise to the old bulb specs. Anyway thanks for your help Jeff, you are the best!

These are the turn signals:
http://www.cb750cafe.com/products-page/lighting-electrical-gauges/dimond-turn-signal-set-qty-4/

Anyway to find a small bulb equivalent of the large stock ones that would fit in there?

 

[jmd_forest]

Try the local Pep Boys for bulbs. They generally have a large selection.

 

[armyofda12mnkeys]

Hey jmd_forest/Jeff, there weren't many exactly 12V small bulbs that fit my socket at Pep Boys.
But I did see a few small bulbs close to 12V so decided to try the '3893 LL' bulb, which was 13.5V (4W).
It worked! Now both turn signals and indicator light are at full power, and the other side doesn't light up anymore.
Thanks!
and Happy Thanksgiving!

 

[jmd_forest]

Glad it worked out for you. Sometimes the easy fix works best.