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Alternator drain?

tarafied1

tarafied1

Well-Known Member
My 93 LX is draining the battery overnight. I can jump start it and it will start. If I trickle the battery it will start within a few hours but overnight it's dead. I put my volt meter on the battery after charging it and I can watch the volts slowly drop, very slowly. If I disconnect the Alt, the voltage drop stops. I had another voltage regulator so I swapped it to see what would happen. Didn't fix it. Do you think I have some bad diode's?
 
is there a way to test a diode? or verify it's the alt? Rebuilt alt's are not cheap. It's been starting fine even after sitting for weeks, now it can't sit overnight. Even with the alt unplugged, when I connect the cables I get some sparks so I am wondering if it could be something else...
 
Start pulling fuses one at a time and check for power drain after each fuse.....or.....shut the damn door!
 
"AzPete" said:
Start pulling fuses one at a time and check for power drain after each fuse.....or.....shut the damn door!
Click to expand...
okay, how do I pull fuses with the door shut?
Moron%20MG.JPG
 
lol......dang....gotta explain everything....pull one fuse....get out of the car....shut the door....read the meter...... Or...remove the seat.

Also, is there an under hood light?
 
Thanks Pete, I'm actually not quite that dumb.
I pulled the fuse for the dome light first, under hood light bulb removed as well.
I pulled all the fuses one at a time (except the dome light fuse which I left out). No effect. I also pushed the door plunger in just in case.
I then started pulling the massive amount of wires hooked to the positive side of the starter relay/solenoid. I found one that caused a draw but low. When I left it unhooked the car wouldn't start (would crank but not run). It goes into a big harness so I couldn't find what it goes to but the EEC test plug is in that harness and the fact it won't run I guess it's part of the EEC.
Anyway the Alt for sure is causing a draw, the other low draw may be a problem as well but I guess I'll start with replacing the Alt.
Advance has one for 79.99...
one funny thing, what is the purpose of a "spare" fuse? #7 is labelled SPARE and had a 15a fuse in it. Why?
foxfusebx
 
Last edited by a moderator:
Gotta kid ya a bit....lol

Spare....like having a spare tire.....they must not have had a spot on the lid for extras like most newer cars do. 17 is also spare...

I doubt they planned for anything extra to be plugged in but you might want to see if there is power at the contacts.

Sounds like your on the right path.
 
The lid has spare fuses in it. Weird. Maybe the box is used in other cars that used that space...
still puzzled, I think I am going to have the battery load tested also
 
I let the car sit overnight with the Alt unplugged, checked bat this morning and it was still fully charged. Pretty sure it is the Alt. gotta recover from Christmas a little and then I will replace the Alt. It can sit for a few weeks.
 
"tarafied1" said:
Thanks Pete, I'm actually not quite that dumb.
I pulled the fuse for the dome light first, under hood light bulb removed as well.
I pulled all the fuses one at a time (except the dome light fuse which I left out). No effect. I also pushed the door plunger in just in case.
I then started pulling the massive amount of wires hooked to the positive side of the starter relay/solenoid. I found one that caused a draw but low. When I left it unhooked the car wouldn't start (would crank but not run). It goes into a big harness so I couldn't find what it goes to but the EEC test plug is in that harness and the fact it won't run I guess it's part of the EEC.
Anyway the Alt for sure is causing a draw, the other low draw may be a problem as well but I guess I'll start with replacing the Alt.
Advance has one for 79.99...
one funny thing, what is the purpose of a "spare" fuse? #7 is labelled SPARE and had a 15a fuse in it. Why?
foxfusebx
Click to expand...

Essentially same thing I did, pulled fuses one at a time, had drain/draw, traced positive from trunk to solenoid, pulled wires one at a time, had drain/draw until I unhooked the Alt, swapped that %#&$ out and havent looked back...
 
Last edited by a moderator:
yep, I'm 99% sure it's a diode or two gone bad. I think when I have the funds I will upgrade the Fox to a 3G alt as well. I just bought a bunch of AC stuff from Waffles and I haven't paid him yet so he is my priority. The Fox can sit for a while. My wife prefers the Expedition anyway. The Fox with it's 2.3L is a little easier on gas than the 4x4 5.4L Expy!
 
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