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I noticed that my Voltage Meter jumps up and down whenever I use my turn signal. It stays above 12V mostly though. Is this normal?
 

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Normal across the board for these cars. And those who know me know I've driven more than my fair share


EricB
 

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None of you smartasses could answer this six months ago, so I'll ask again, in case there are any new smartasses who can answer this time.

If the voltmeter jumps with the turn signal, how come it doesn't also jump with the 4-way flashers? Surely they use the same bulbs and all. Anybody got a reasonable answer?
 

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I'll see if I can some up with a smart-ass-enough response for you
Since you are only flashing the lights on half of the car with the blinkers, it knocks things crooked and outta whack. But with the 4-way hazards, all lights are flashing simultaneously, keeping things in balance. The directionals cause the right side (or left side) of the car to get heavier (more light on that side), thus drawing more energy...

hehehehe

Truly, though, no clue. As integrated as everything in these cars are with everything else (i.e., unplug one of the 2-3 dozen black box "computers" and you never know WHAT will go wrong), it doesn't surprise me that the directionals cause a temporary "dip" in the signal being sent to the voltage meter as the turn signals are probably using a totally different relay system than are the individual tuen signals. The 4-way relay system doesn't have effect. Just one of those little anomolies that we live with and take for "normal"...

EricB
 

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How's this sound for a reason...
The Hazard light circuit draws it's power from the battery, so you can pull the keys and walk away if you're broken down. The Turn signal uses the same flasher but gets it's power from the alternator, since who cares if the turn signal goes out once you shut the car off.
The alternator, being regulated, takes a moment to adjust to the new load (as the lights turn on and off) were as the battery, being a fixed 12v source, runs them with no problem.

Either that or the Fat Bastard in the driver's seat is lowering one side of the car more than the other, causing a "ground un-balance". I'm sure it's one or the other...

Steve ;^)
 

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How's this one?

I would think most people only notice the voltage drop when waiting to turn at a light. During this time the brake lights are on.

In the case of emergency lights, you either are on handbrakes or nothing at all. Hence the battery (and/or alternator) can keep up.

Alternator current supply and battery strenght all play factors in this.

Whooo hooo! :)

later,
Amir
93 TT
 

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Okay, now Amir here has the weakest of all the arguments. It sounds plausible and shows good lateral thinking (if he can just crank that back another 90 degrees, he could be a manager where I work), but the hypothesis that associates using the turn signals only simultaneously with the brakes is largely false in my case. I enable my brake lights only if there is a cop behind me (a home-made option that is barrels of laughs when you have tailgaters), so I rarely have the turns and the brake lights on together. I first noticed the meter jumping when I was making a lane change, no brakes involved.

I believe SUTHNR to have opined that the turn signal involves a load/no-load cycle (true) but that the hazards use a load/load cycle (false - all 4 are on at the same time, and then all four go off at the same time. There is no balanced alternation between front/rear or left/right, although there's really no good reason why there couldn't be).

As for Steve, I have new struts and springs, so I think that we can rule out the "ground un-balance" theory. Besides, the Hershey bars are almost gone now, so get off my back already.

I wonder what the voltmeter looks like when you're watching a DVD while you drive?
 
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