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Discussion Starter #1
Hello All,
I purchased a 2008 DR650SE last winter. After some adjustments it runs great, but I recently got around to installing turn signals, and they won't flash. When I attempt the signal, the corresponding bulbs remain lit until I cancel the signal. The signals are standard, not LED, the flasher is the OEM unit as far as I can tell.

Based on my online research, it is either:

A.) Flasher relay is bad, and must be replaced
-or-
B.) Insufficient load to trigger the flasher relay, caused by a poor connection or wire (or use of LED signals, but mine are not LEDs).

I have NOT been able to determine, though, what readings I should see at the relay to determine if it's still good. I'd rather not replace the flasher relay if it's still good, or spend hours chasing a short if the relay is bad. Does anyone know what the proper readings are to indicate a good or bad flasher relay?

Thanks,
Patrick
 

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If the bulbs light up as they should try to tap on the relay and see if it blinks. If it is the round type with 2 terminals like on a car, you should see battery volts on one side, and also see it on the other side til it gets a load and blinks. If it is a 3 wire type, maybe an electronic flasher it will be about the same but with a ground wire on it also. Tapping may get it to blink once or start working.

Are the bulbs wired correctly so the high brightness filament is lighting up?
on a 1157 bulb the running light filament draws about less than 1 amp, but the turn filament draws 2+ amps. So it may be a lack of current draw if they are not correct.
 

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Discussion Starter #3
If the bulbs light up as they should try to tap on the relay and see if it blinks. If it is the round type with 2 terminals like on a car, you should see battery volts on one side, and also see it on the other side til it gets a load and blinks. If it is a 3 wire type, maybe an electronic flasher it will be about the same but with a ground wire on it also. Tapping may get it to blink once or start working.

Are the bulbs wired correctly so the high brightness filament is lighting up?
on a 1157 bulb the running light filament draws about less than 1 amp, but the turn filament draws 2+ amps. So it may be a lack of current draw if they are not correct.
I will check on the relay tonight. The bulbs themselves are only two-wire, single-filament, so they do not feature a running light.
 

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Then they will have to be 1156 bulbs to have the necessary amp draw for the flasher to work. If they are 89 or so they are too low current draw.
 

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Discussion Starter #5
In theory, wiring a resistor in series with the bulb would increase the draw sufficiently to test that the bulb is the issue, correct? What resistor range would you recommend?

Given that V=IR, V=12volts, required increase of I = 2amps, I would think a 6 ohm resistor would do the trick? (My background is in ME, not EE, so I don't want to make too many assumptions here.)

Thanks for taking the time to help!
 

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Discussion Starter #6
In theory, wiring a resistor in series with the bulb would increase the draw sufficiently to test that the bulb is the issue, correct? What resistor range would you recommend?

Given that V=IR, V=12volts, required increase of I = 2amps, I would think a 6 ohm resistor would do the trick? (My background is in ME, not EE, so I don't want to make too many assumptions here.)

Thanks for taking the time to help!
Also, by the same logic, the resistor would need to be capable of handling roughly 30 watts, correct?
 

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I am an old auto mechanic so I don't do electrical formulas well. But have dabbled in electronics.I think you are right about the resistance and wattage capacity. It would be an easy test to see if that is the problem. But if you have lower wattage bulbs are they going to be bright enough to be seen in daylight? Thinking safety.
 

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Discussion Starter #8
I am an old auto mechanic so I don't do electrical formulas well. But have dabbled in electronics.I think you are right about the resistance and wattage capacity. It would be an easy test to see if that is the problem. But if you have lower wattage bulbs are they going to be bright enough to be seen in daylight? Thinking safety.
Ah, this is a good point. I think I'll take the signals off of another bike and wire them in just to confirm that the flasher is still good, then I'll spend the money on brighter signals. I'll post back with the results.

Thanks for the help!
 

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Good idea to be seen . I was coming toward a rider a few weeks ago and watched him slow and turn left in front of me, across my lane, which was fine because we had plenty of space. But I was surprised because I didn't see his turn signal until he was turning and closer. I think they were smoked and not very bright. So I am concerned about visibility.
 

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Discussion Starter #10
Good idea to be seen . I was coming toward a rider a few weeks ago and watched him slow and turn left in front of me, across my lane, which was fine because we had plenty of space. But I was surprised because I didn't see his turn signal until he was turning and closer. I think they were smoked and not very bright. So I am concerned about visibility.
Yeah, definitely. I've been thinking about converting to a 3-wire setup with running lights, so it looks more like a motorcycle and less like a car with a headlight out at night. But that will be a project for another weekend.

Anyway, last night I dug out some old 90s Kawasaki stock signal units I had laying around in the garage and wired both of those in series with the two newer, possibly lower draw units. The voltage drop was enough to dim all of the lights, so I'm fairly certain the resistance was sufficient and it still did not flash, so I think the relay is probably bad. I'm going to replace that this evening after work and see where that gets me.
 

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Discussion Starter #11
Dropped in an $11 electronic relay from Napa and it works flawlessly - the signals are as bright if not brighter than stock. So I think the old relay was just no longer functioning.

Thanks again for the help!
 
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