Turn Signal Problem/Fix

[djalbin]

My 94 FZR1000 developed a problem where the left side turn signals (front/rear) worked fine but the right side turn signals did not work. The turn signal indicator on the console was on all the time (although it would flash when using the left turn signals). The right front turn signal was on all the time (normal except it would not flash). The right rear turn signal would not light at all. Since the left side is working OK I figured the flasher relay is OK and it's the right rear turn signal that's causing the problem (bad bulb); so I removed the lens to inspect it. The filaments of the bulb are fine but the plastic housing surrounding the base of the bulb is melted to the base of the bulb. Obviously there was enough current to melt the plastic and open up the contacts in the housing. No fuses were blown, so there were no electrical shorts or high current flowing through any other components (it just toasted the one turn signal housing).
The rear turn signals are aftermarket so I found a replacement set and mounted/wired them in. Left side turn signals still work OK. Right side turn signals are now on all the time without flashing. The turn signal indicator on the console is on all the time. The right front turn signal is on all the time. The right rear turn signal is on all the time (at least I'm now getting light from the right rear turn signal).
So now it seems the problem is either the flasher relay or the right front turn signal bulb. I unplug the connector from the flasher unit and it appears normal. I apply dielectric grease to the contacts and plug the connector back in. No change to right side turn signal behavior. I take the right side front turn signal bulb out, inspect it (filaments are OK), and put it back in. No change to right side turn signal behavior. I didn't have any replacement bulbs so I swapped the front turn signal bulbs (left to right and right to left) to see if the problem moves with the bulb (from the right side to the left side).
Everything now works normal. Left side and right side turn signals (front/rear), and turn signal indicator on the console, are all working normal.
How the right rear turn signal could melt itself without blowing a fuse is a mystery. Replacing the rear turn signals was obvious. How switching two identical bulbs in the front turn signals could fix the problem is a mystery.
Moral of the story ... electrical problems on motorcycles are mysterious freaks of nature.

Don

[FZRDude]

Didn't OBurn have a similar problem with his tail light?

[DAVE]

Check the wattage of the globes. The usually require at least a minimum size (I think 21w) in both front and rear to flash properly. If less they will stay on all the time. This is to warn you that there is something wrong with your indicators.

How the right rear turn signal could melt itself without blowing a fuse is a mystery. Replacing the rear turn signals was obvious.

A bad connection creates hi resistance and heat is concentrated in a small area when current passes. The fuse will not blow unless the live wire passes too much current, i.e. a short

[djalbin]

Dave,
That's what I assumed with the melting. The resistance increased and turned the socket into a mini toaster until the resistance became infinite and completely opened the circuit. Shorting the circuit would have blown a fuse. The globes (bulbs) are the proper wattage and have worked for the last 6 months to a year in the bike; that's when I went through the experience of getting the correct wattage bulbs installed in order to get the turn signals to function properly. I could not find any specs for the bulbs in the service manuals. The only reference I found was in the FZR1000 F/C Owner's Manual (12V/27W for rear flasher light and 12V/27W/8W for front flasher position light). The front bulbs are still the same bulbs that have been in the bike all along. All I did was swap them right-to-left and left-to-right. Maybe the right bulb was not making a good contact in the socket. Switching them may have either wiped the contacts enough to correct the problem, or there may be just enough variation in the sockets and bulbs that one bulb fits (makes contact) better in one socket versus the other.
It's still funny that the fix was not complete until after swapping the front bulbs.


Don

[DAVE]

Your right Don, bad contacts would cause the flasher problem.
I work as an electrician at a paper manufacturing plant (nearly 30 years) and have seen many times the results of bad connections, particularly on high power equipment. The results can be quite often spectacular.

These days we do thermal imaging all our electrical gear regularly with an infra red camera. You can see the hot spots developing before they become a problem. Sometimes it's just a matter of cleaning a fuse connection or bolted joint, or commonly a faulty crimp lug has to be cut off and replaced.

The other big problem is water or steam getting in to electricals. The same can be said for bikes as it causes corrosion and/or electrolysis, eating away at vital connections.

With bikes the other problem you can encounter is the PREVIOUS OWNER. I found my headlight globes were inserted upside down. High beam was ok but low beam was shining into the sky.