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Passenger side turn signal blinking fast when headlights are on?

9K views 5 replies 6 participants last post by  SledDog 
#1 ·
For that past two weeks or so, I've noticed that a few times when my passenger side turn signal blinks really fast. I didn't make the connection until today, but I discovered that it only does it when the headlights are on. I don't have a lamp failure indicated and it looks like all of the lights are blinking. Is it just a bad flasher? Seems strange that it happens only when the headlights are on.
 
#2 ·
It could be a bad ground. Power does strange things when the ground..........

is weak. Since that whole area is plastic, there has to be a seperate ground wire. I'd check there first..[?]
 
#6 ·
Most of the systems work by detecting low current, then indicating that something is wrong. A broken or burnt out bulb typically draws little to no current. A bad ground or a loose connection can cause the bulb to draw less than normal current. This is why if you change to LED lights, you need an "adapter" to increase the current draw so the system doesn't think a bulb has blown.

Thinking about it, it is likely that the front passenger bulb on Brian's car has partially failed. The 1157 bulb is a dual filament bulb. The second filament is proably only used when the headlights are on. The first filament is probably ok, which is why the bulb looks like it is working correctly when in fact it really isn't. At least this is another possiblity that is pretty easy to test out. If you take the bulb out, you can probably see if the filament is ok or ohm it out.

Remember You can always trust your mother, but you can never trust your grounds.[:eek:)]
 
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