Turn signal problem solved

[The_Eman]

Simple solution but I would have never figured it out on my own if I hadn't searched and read other FORDification threads.

68 F100

Flashers worked, brakes lights worked but the turn signal did not flash. The turn light on all four sides did illuminate though. I changed the flasher located deep deep under the dash and problem solved.

The only kink I have is, I bought a "loud" flasher at Auto Zone because it was the only one that would handle the 14Amp and cross referenced the 536. I am getting some back EMI into the amp meter and the amp meter needle flashes/moves in step with the turn signals. I am going to buy another flasher from either lmc or dennis carpenter which should fix that problem.

[fordman]

in my opinon you are rigth and wrong. yes it should daw power from the system. but not enough to make the light come on. the light is a warning that voltage is low. if voltage drops that low with just turning on the bliker then ther is a loss some place else to find. but i am not sure that is his problem.

[rjewkes]

with full instrument yes. the needle will move in time with the blinkers even when running exccept maybe at higher speeds when the load is less than the charge.

I've never realy looked at my amp needle and flasher lights at the same time at highspeeds though i'm ussauly watching the road then. for a dummy light no it mshouldn't flicker with the turn signals on. And its not your fuse there.

you have something either wired up backwards or a bad volot reg or missing charging exciter wire somewhere.

[The_Eman]

You gents have me confused now. Maybe the needle moving in time with the blinker is a power draw problem and doesn't have anything to do with EMI. The flasher is rated at 14A so it does draw some power.

The needle does move significanlty back and forth though. Is this normal, for the ammeter to move like that?


Eric

[The_Eman]

At normal operation the needle rests half way between D and C. When the turn signal is engaged the needle moves approximately 3/4 of the total distance to the right or the C direction. Almost all the way to the right.

I really think the flasher I bought is causing some interference due to the hard switching noise. If there was a power drain I believe the ammeter would move towards the D. It never does. Right turn or left turn signal the needle moves towards the C.

[kid]

Before you buy any parts look at this little idea. Each bulb draws 15 Watts at 12 volts so they use 1.25 amps times 2 bulbs. But they are fed through a 16 gauge wire that requires another 2 amps because of voltage drop. The ignition switch is fed through a 10 gauge wire that is probably connected through 10 ohms of resistance caused by corrosion. Ohms law says 1.2 amps. Switch contacts and other corrosion gives you another amp. So at at an idle the alternator is only putting out 5 amps. So every pulse uses 2.5+2+1.2 that comes to 6.7 amps. The needle has to swing it measures in and out current to the system. The alternator is also trying to charge the battery at the same time and is losing the battle. We still have not added in the Radio and whatever else is on. Moving 2.4 amps all of a sudden makes the needle move. Stare at the needle and turn on the lights. It drops. Same when you turn the radio on. The meter reads the difference between what is going into the battery and what is coming out. Not an actual value so the amount of the change is more at low RPM and less at high RPM when you move 2.4 amps.

I use the Loud variable voltage flashers so I can still work if bulbs are out or bulbs become LEDs.

[fordman]

man that needle moves alot just for a turn signal. i thought you just had a dummy light in the dash i didn't realize it was a guage.

[rjewkes]

yeah i heard you had a light for some reason.

that was lit all the time or is that another member?

kids right, i will never know with mine as i beleive my ammeter has been bypassed as the needle never moves but i'm never outa battery juice.

[fordman]

come to think of it. if the needle is going over to the charge side when the blinker comes on that is good. it menas the alt is charging. if it were to go to Discharge that would be bad. maybe the thing on the back of the cluster is out of adjustment. is your gas guage reading correctly?

[rjewkes]

mine? yes it is when i fill it from empty with 9 gallons it lines up on half a tank.

[fordman]

i was asking eman what his read. sorry.

[rjewkes]

ok i know my shunt has been unwired but atleast i still charge.