| Author | Message | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 1104 Registered: 11-2002 |
>>It is the investigation into incidental findings that kills more people, either as complications of the investigation, or in treating a non-issue.<< LOL | ||
| James Selevan (Jselevan)
Member Username: Jselevan Post Number: 436 Registered: 6-2002 |
Mike - .25-volt drop with turn signal is insignificant, and normal. In medicine, we refer to this as an incidental finding. It is the investigation into incidental findings that kills more people, either as complications of the investigation, or in treating a non-issue. If it ain't broken - don't fix it. Jim S. | ||
| Shamile Shams Kassam II (Shamile)
New member Username: Shamile Post Number: 9 Registered: 12-2002 |
To Verell, Um....wow Shamile Shams Kassam II | ||
| Verell Boaen (Verell)
Member Username: Verell Post Number: 592 Registered: 5-2001 |
BTW, The current surge when the turn signal blinks is mostly due to the bulbs themselves. a tungsten filament that's off (ie' cool') has only about 1/10 the resistance of a hot filament. Thus a 12Watt bulb that draws 1A when it's on, will draw ~10A the instant it's first turned on, decreasing rapidly (~50mSec or so) to it's hot current. So if you're flashing 6 12W bulbs, the surge current could be 60Amps! (And you were wondering why your voltage was dropping!) In practice, wiring, switch, & flasher contact resistance all reduce the turn-on surge current, somewhat, but the surge is still 3x - 5x steady state! (I'm remembering the on:off current from analyzing the drive current for a DEC 11/45 console bulbs back in the mid 70s to see why the light bulb drive transistors were failing at a high rate. (Lamp surge current was ~3x the transistor's max current!) My numbers could be off a bit, but the concept is still valid.) | ||
| John_Miles (John_miles)
New member Username: John_miles Post Number: 42 Registered: 7-2001 |
Sounds like you've hooked the voltmeter into the turn-signal circuit.  You're measuring the voltage drop across the wiring to the turn signal bulbs, most likely (I*R, where I is not too great but R may be fairly high because they won't be using very heavy wire for this particular circuit). If you check the voltage at the battery with the engine running, you probably won't see any movement related to the turn-signal bulbs. | ||
| Mike Procopio (Pupz308)
Junior Member Username: Pupz308 Post Number: 139 Registered: 10-2002 |
The voltmeter is grounded directly from a lead run from the battery. The voltage source is coming from the fusebox, after the fuse, on the one "switched" voltage source I was able to find, I believe it's the 5th fuse from the left on the left most fuse box... I'd run it directly from the battery, but I would prefer a switched voltage source... I'll try connecting it directly from the battery when I get a chance, and report back. | ||
| Paul Hill (348paul)
Junior Member Username: 348paul Post Number: 94 Registered: 12-2002 |
Mike, Put the voltmeter on the battery and try! It�s the resistance in the wires under load. All cables suffer voltage loss under load. There is a capacitor in the flasher relay that takes quite a bit of current. As John said - where did you connect the voltmeter? - If it is under the dash somewhere it is bound to be because of the above. Paul | ||
| John_Miles (John_miles)
New member Username: John_miles Post Number: 40 Registered: 7-2001 |
The voltage fluctates when I use my turn signal! I estimated by .25 volts, and confirmed this with a digital voltmeter. When the signal lights up, it drops, then when it goes out, the voltage returns. I would make a crack about the Italian parliament never having ratified Ohm's Law, but... believe it or, not my Y2K Honda Accord is even worse when it comes to accessories causing unreasonable amounts of voltage drop. Where did you connect the voltmeter? | ||
| Bruno (Originalsinner)
Intermediate Member Username: Originalsinner Post Number: 1002 Registered: 5-2002 |
Welcome to the wonderful world of Itailian cars. Check the archives under fuse box for a start. You'll find plenty from there. | ||
| Mike Procopio (Pupz308)
Junior Member Username: Pupz308 Post Number: 138 Registered: 10-2002 |
I recently installed a voltmeter in my 308--it has been great. It's brought my attention to something strange... The voltage fluctates when I use my turn signal! I estimated by .25 volts, and confirmed this with a digital voltmeter. When the signal lights up, it drops, then when it goes out, the voltage returns. What in the WORLD is wrong to cause that kind of a voltage fluctation from a turn signal? Do the turn signals have that significant of a current draw? This happens when the car is running, by the way... Normal output is 13.8V at 1500RPM. I would expect the voltage regulator in the alternator to address this situation and keep the voltage fairly constant (though the turn signal may be switching on and off for the VR to be effective). Any ideas on what could be causing this? |