Batteries draining over night

soggybottom

Full Access Member
Joined
Nov 13, 2012
Posts
53
Reaction score
0
Location
eau claire wi
Lately if I leave the truck sit for more than a day and try to start it my batteries are dead. Tried a parasitic drain test and found that if I remove the large black and orange wire from the solenoid on the passenger fender, the drain goes away. This wire goes to the alternator, so I disconnected it from the alternator, and still have the same draw on my batteries. :confused:

Anyone know what else this wire goes to, or have any idea what the drain could be? Thanks.
 

franklin2

Full Access Member
Joined
Feb 24, 2009
Posts
5,161
Reaction score
1,385
Location
Va
The the diagram shows several black/orange wires fed by green fusible links. One goes to the alternator output like you mentioned. The other goes over and feeds the glowplug circuits. The other one is shown feeding the always hot part of the fuse box. The always hot part of the fuse box feeds the cigarette lighter, the running lights, electric shift control, and courtesy lights.

To eliminate that wire being the one for the fuse box, you could set your drain test up, and pull fuses 4, 8, 12, and 16.
 

soggybottom

Full Access Member
Joined
Nov 13, 2012
Posts
53
Reaction score
0
Location
eau claire wi
I tried pulling all the fuses in the box, and still had the same draw. I guess I'll have to start tracing wires and see what I find. Thanks.
 

Compu Doc

Full Access Member
Joined
Jun 5, 2005
Posts
1,271
Reaction score
2
Location
Middletown NJ
Have you felt the alternator when the engine is cold?. I had that problem one time and the alternator was warmer than the rest of the engine when it sat overnight. Replaced the alternator and all was well.
 

Agnem

Using the Force!
Supporting Member
Joined
Jan 10, 2005
Posts
17,067
Reaction score
373
Location
Delta, PA
Disconnect both negative terminals of your batteries. Connect an alligator clip lead between one negative post and your negative terminal. This was necessary so that your electronic equipment can boot and charge any filter capacitors. Connect an amp meter (10 amp capability) in parallel with the clip lead, and then remove the clip lead. Measure your amp draw. Let us know what it is. We can then start looking at components capable of drawing that amount of juice. If you don't do the clip lead thing, you run the chance of blowing the fuse in your amp meter.
 

laserjock

Almost there...
Supporting Member
Joined
Nov 20, 2012
Posts
8,841
Reaction score
3,129
Location
Maryland
Just went through this with a subaru. Mine was the alternator. Next thing I would do (aside from what Agnem said which is absolutely right) is to unhook the starter cable. Check your draw. Might do the starter cable first just because its easy. Not a lot of things left that can draw power if you have the fuses out and the alt unhooked. I was about to start tearing the wiring harness out of the car when it dawned on me to unhook the alternator. Same situation. All the fuses out. Still had the draw. Since you have done that already, starter is about all that's left unless its like the GP controller/ciruit.
 

argve

Resident Fruitcake
Joined
Dec 11, 2004
Posts
7,510
Reaction score
32
Location
Gwynneville, Indiana
he said he unhooked the alt so with it unhooked it can't be the alt.

As Mel recommened start getting the amp draw reading from all the wires that feed the trucks electrical system. I had it once where the relay for the TECA (Transmission Electronic Control Assembly) or PCM or TCM depends on your lingo... the contacts on it were burnt shut (closed) so the transmission control on my E4OD was always on and it would kill both batteries overnight. Found it with a clamp on amp meter that could read DC amps, but noticed that if made and unmade the connections on the battery I could hear a solenoid click in the transmission so that started me looking on the drivers side for power consumption.
 

laserjock

Almost there...
Supporting Member
Joined
Nov 20, 2012
Posts
8,841
Reaction score
3,129
Location
Maryland
Yep. Like I said mine was the alternator. I see that he has unhooked his. I thought I would mention a couple other quick places to look before he starts pulling wire out of the truck because I was there myself trying to figure out my issue.
 

Ed3117

Registered User
Joined
Nov 28, 2012
Posts
1
Reaction score
0
Location
Astoria, Oregon
Had this exact thing happen to me a few weeks ago. Drove from Astoria to Walla Walla, then up to Wenachee for Octoberfest in Leavenworth. About halfway to Wenachee, I notice that my battery gauge has stopped reading 13-ish volts and is now reading barely 8. Knowing how notoriously inaccurate the factory gauges are, I didn't really pay any attention, although the truck did seem maybe a little bit more sluggish cranking over after the one snack stop we made...

Next morning I go to start the truck and I get maybe two cranks and it's dead. Walked to an Auto Zone and borrow their jump start box. Get the truck started and drive to the Auto Zone and pull the alternator to get it checked (thinking that maybe it had quit charging). Alternator was good. Pull the batteries to get them recharged inside and while I'm waiting I pull the regulator plug off the regulator (on the passenger side fender...little shiny flat box) and a couple of the plugs are corroded over with rust. Cleaned up the harness' plug and replaced the regulator with a new one ($16 and in stock at the Auto Zone), put the batteries back in, fire it up, and I got my 13 ish volts back; both on the gauge and on a multimeter across the batt terminals. Has been charging fine for the 1200 odd miles since.

So you might try the regulator...not advocating shotgun maintenance, but a regulator is only $16 ;Sweet

Ed

Edit: My 87's alternator is of course externally regulated. Not sure if or when Ford went to internally regulated alternators on these trucks...I'm sure one of the guru's would know...
 

franklin2

Full Access Member
Joined
Feb 24, 2009
Posts
5,161
Reaction score
1,385
Location
Va
Had this exact thing happen to me a few weeks ago. Drove from Astoria to Walla Walla, then up to Wenachee for Octoberfest in Leavenworth. About halfway to Wenachee, I notice that my battery gauge has stopped reading 13-ish volts and is now reading barely 8. Knowing how notoriously inaccurate the factory gauges are, I didn't really pay any attention, although the truck did seem maybe a little bit more sluggish cranking over after the one snack stop we made...

Next morning I go to start the truck and I get maybe two cranks and it's dead. Walked to an Auto Zone and borrow their jump start box. Get the truck started and drive to the Auto Zone and pull the alternator to get it checked (thinking that maybe it had quit charging). Alternator was good. Pull the batteries to get them recharged inside and while I'm waiting I pull the regulator plug off the regulator (on the passenger side fender...little shiny flat box) and a couple of the plugs are corroded over with rust. Cleaned up the harness' plug and replaced the regulator with a new one ($16 and in stock at the Auto Zone), put the batteries back in, fire it up, and I got my 13 ish volts back; both on the gauge and on a multimeter across the batt terminals. Has been charging fine for the 1200 odd miles since.

So you might try the regulator...not advocating shotgun maintenance, but a regulator is only $16 ;Sweet

Ed

Edit: My 87's alternator is of course externally regulated. Not sure if or when Ford went to internally regulated alternators on these trucks...I'm sure one of the guru's would know...

Yours was not charging. His is a drain problem. Two different problems requiring different solutions. In the very beginning which problem it is needs to be determined, but I think he has determined already it's a drain problem.
 

soggybottom

Full Access Member
Joined
Nov 13, 2012
Posts
53
Reaction score
0
Location
eau claire wi
I tried unplugging the regulator, and saw no change in the draw. I have just been using a test light to run the test. I guess I could do it with my multimeter, but will it make any difference?

Unfortunately, I won't be able to work on it again until this weekend, work is crazy right now. Guess I just have to keep disconnecting that wire overnight.

Anyone know how to disconnect the large harness at the firewall? Looks like just a bolt through the middle?

I appreciate all the help
 

argve

Resident Fruitcake
Joined
Dec 11, 2004
Posts
7,510
Reaction score
32
Location
Gwynneville, Indiana
Yes using a multi-meter will tell you more information because there are some things that continue to pull current at all times like the memory for the clock on the radio. But it's not much. also if you have an underhood light and it's on, then naturally that will be pulling some current. But if you unhook the radio and under hood light (if you even have one) then nothing should be consuming power if memory serves.
 

TronDD

Full Access Member
Joined
Mar 8, 2013
Posts
151
Reaction score
0
Location
MA
My battery drain problem was the glow plug wires melting the engine connector internally causing an intermittent short inside.

I found it when it spread to the FSS and I couldn't shut the engine off one day.

Tim.
 

laserjock

Almost there...
Supporting Member
Joined
Nov 20, 2012
Posts
8,841
Reaction score
3,129
Location
Maryland
I'm not sure how you look for a power draw with a test light. That is only going to tell you that you have a complete circuit when you touch it from what you are testing to ground. You really need an ammeter or a DMM that measures current. Am I right??? It's early and I haven't had my first Dew of the morning yet.
 
Top