k,
with the key out

how much should the system draw from the battery???

trying to find a short, but im confused about how much current should be drawn if thres KAM and other "idle" systems.......

also, if i put my meter on voltage, and in series with the neg post and the neg clamp, how many volts should i read after the inital computer "spike"???

thnx
lala

oh sorry, 94 ranger 2.3 xl 2wd

 

I would think about 0.05 amps at the most.

You test voltage in parallel.

 

well, with a 41 mA draw, my battery discharges overnight.

even though i tried finding the short by testing the resistance across the posts, it gave me inf resis, and reverse wise, i got like 500 ohms, showing the rectifier diodes...

a friend suggested that if i took a multimeter or a test light in series with the beg post and clamp, with the key off, i should get no light, or significantly less than 12, but how much less, he did not know. after pulling several fuses, i got the drop to go to like 3 volts, but im confused, it almost seems like theres a short in three places for this method. 40 mA shouldnt drain a battery overnight, and i know its not the batter because i load tested it and replaced it twice... sigh

ne clues guys? these wiring harneses can be a nightmare!

lala

 

Is your alternator working properly? That drain is normal.

 

thats the thing! i watched my friend (who owns an alt/genrator/starter repair shop) spin up the alternator in front of me on a bench tester! the output was solid,strong and steady. Even putting a meter on it to see for a short was giving me the right values. This all began when i rebuilt the alternator, but even after a mechanical/electrical bench test, the alternator passes!

the rebuild replaced everything but the 6 diodes across the field coils, yet those diodes checked out fine. man, im so frustrated, cause i seem to have done everything right, and its still wrong! oh well, at least it still summer!


lala

 

Can you borrow a battery from a friend and see if it still happens, my last idea.

 

got it

weel, it wasnt the battery, although i had replaced it previously

turns out, it has something to do with the fuse regarding the interior light/radio/voltmeter guage/tach. once the fuse was pulled, the draw dropped to 3 milli ampere and now the truck starts again over nite. I compared this reading to my friends 95 b2200 and it was about there with a draw of 2 millies. so now its no longer a mistery , just the tedious task of analysing those few simple circuits.

ken00, are you sure the factory draw of 40 millies is correct? after doing some math i figured, well, 40 millies is 144 amp hours, which is alot, where 3 millies gives you 10.8 amp hours. a standard batter usually gives 650 amp hours max. Please someone confirm this as to my math is shotty at best at 6am.

thanx to all for you help,

lala

 

I checked my Ford manual.....

«2000 Ranger Table of Contents»
«Group 4: Electrical»
«Section 414-00: CHARGING SYSTEM — GENERAL INFORMATION»
«DIAGNOSIS AND TESTING»


Charging System


Component Tests


Battery — Drain Testing

Check for current drains on the battery in excess of 50 milliamps with all the electrical accessories off and the vehicle at rest. Current drains can be tested with the following procedure.

WARNING:
Do not attempt this test on a lead-acid battery that has recently been recharged. Explosive gases can cause personal injury.

CAUTION:
To prevent damage to the meter, do not crank the engine or operate accessories that draw more than 10A.

Note:
Many computers draw 10 mA or more continuously.

Note:
Use an in-line ammeter between the battery positive or negative post and its respective cable.

1. Turn the switch to mA/A dc.

2. Disconnect the battery terminal and touch the probes.

3. Isolate the circuit causing the current drain by pulling out one fuse after another from the fuse junction panel while reading the display.

The current reading will drop when the fuse on the bad circuit is pulled.

4. Reinstall the fuse and test the components (including connectors) of that circuit to find the defective component(s).

The current reading (current drain) should be less than 0.05 amp. If current drain exceeds 0.05 amp, a constant current drain is present. (Underhood, glove compartment and luggage compartment lamps) that do not shut off properly are all possible sources of current drain.

l If the drain is not caused by a vehicle lamp, remove the fuses from the interior fuse junction panel one at a time, until the cause of the drain is located.

l If the drain is still undetermined, remove the fuses one at a time at the power distribution box to find the problem circuit.

 

weel, looks like both batteries are SNAFUED, but i'll have to reconfirm the second one when i get off vacation. get ahold of you all soon, after france... heheh


lala