Problem... my ford f100 has a parasitic battery drain....enough that it pulls the battery down to 6 volts over night...so I've been going through the wiring....looking at the alt I noticed that the power wire was going to the number 1 spade... and it should be going #2 and @ 2 spade was going to the loom into the dash,,,,, my guess is it the gen light???.... so trying to think back.... I remember taking a piece of wire wrapping it around a Phillips and making a little coil and plugging it in to both spades,,,, seem like it worked well ???? So I un hook the plug. and just plugged the power wire to #2... started it up 14.2 volts... and shuts off with the key.... seems to me I remember the #1 spade doesn't even have to be hooked up.. but if you use it it either has to be hooked up to the gen light or acc power or the truck won't shut off.... not sure that the alt wired wrong was my problem.... my gauge doesn't show an amp draw... and waiting till tomorrow will tell....my idea is that hooked wrong keeps the alt energized ??? what say you... is it ok to not use #1 spade
Usually jump battery terminal to #2 and then #1 is powered by the ign either thru the indicator light or diode if using a voltmeter. Don't think it will charge if #1 isn't used.
the question I still have is if the battery wire is hooked to #1 instead of two... would it keep the sensor energized and drain the battery?
I don't understand??? if it was shorted would it still charge 14.2 volt in the battery when running???
heres what i think, and would be easy to test... turn the key to on... but not start.... the #1 would light the test light... as soon as the motor is started.... the light would go off.....with the wires hooked backwards the sensor would be hot all the time,,,,, correct???
Battery hooked to #1 would be a draw. Wired correctly and you turn the key; but didn't start it, there would be power at #1. Once started, there would still be power at #1. That's why you need a light bulb or diode in line*; otherwise it back feeds the ignition and the engine won't shut off. * Or some other way to isolate #1; such as wiring it to the accessory terminal on the ignition switch.
A diode is a one way valve. So, (if wired correctly). it can charge while running, but will discharge while you sleep if its bad
I think thats close...but will check today...and I think it'll work fine with out the #1 hooked up... but I will do a test today...., if the battery didn't die over night... I think the # 2 has battery sleep volts... same as # 1...which is 12.2 volts or less.... when you spin the alternator the volts go to 14.2... when that happens it shut power to # 1.... and if the alternator starts going bad and puts out less than 12.2 while spinning... #1 lights up.... the only thing I see happening if you don't hook up the #1 wire is without a volt meter you would not know that the alternator quit charging...
Well... good news... sat over night and still at 12.2v..dark out so didn't do the alternator test... but I think alls good... took a minute to find the battery draw..... but found it...
I save every usable wiring diagram I find on my photobucket page and for 10 / 12 SI most of them are pretty close to the same. No diode or idiot light in the exciter wire usually causes the "Won't shut off when I turn the key off thing, that we get a call from a buddy who just put on on his car. A blow diode is often the cause of a drain. They can be checked with a scope that is designed to check them but for most of us it is take the alternator apart and check the diodes with an ohmmeter. The common hookup. That I have used a dozen times. The same thing drawn out
Yes - but it will cause a drain while parked. The Alternator makes AC voltage. Simply the diodes just block the + volts going to the negative side and the - volts going to the + side making DC. Diodes are basically a 1 way valve when it shorts voltage can p*** both directions.
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