Electrical, please help..

[Dinnygee]

I severely need guidance on this one...
Please bear with me as this will be a little long winded, and I don't know what half the **** means...
To a point, I understand what the starting and charging system do, but I have little automotive or electrical experience....

To begin, my truck starts properly, never had any issues with crank or start that I recall, ever.
I do have an after market radio, but the head unit is currently disconnected and sitting in the back seat.

I've already confirmed (via bench test at local oreilleys, where everything is under warranty still) that the battery, the alternator, and the starter are all functioning as they should. Battery is about 2yo, alternator about 5yo, and I replaced the starter yesterday.

My issue is when my truck is running, I'm slowly loosing battery volts..
With a multimeter, I've checked the alternator and starter when key is in ON position. I've also checked all of my fuses in my door panel, and the small fuses in the box next to my battery. They're all reading what they should, except for 5 of the fuses in my door panel.. I'm not sure how they would be related to each other, but in case that's important I'll include the numbers and descriptions. Instead of reading what my battery level was at, for exampleit was at the time 12.48 volts, these 6 were reading at 160 to 190 volts.
(I've since pulled out ALL BUT #4 and #8 to see if that would fix the drain issue, it hasnt)

Door panel fuse box #s:
#3 Trailer tow right-hand stop / turn lamp
#4 Starter
#7 Trailer tor left-land stop / turn lamp
#8 Cluster, Audio, GEM
#31 Rear audio control
#32 Auxiliary center high- mounted stop lamp

I'm hearing it could be the ignition switch. (Do I have to have a memory saver for a 2003 Ford explorer sport trac XLT 2.0 2WD 1st gen?) Which I was going to replace today.. until I was reading up on it and found I might screw up something with programming...

I am in a pinch because I'm not in the position to buy something new, so I need this thing to keep running for now.. and I've realized I'm in way over my head. I'll be as active as I can possibly be on here, since my main source of transport hasn't been able to get me anywhere else..

Has ANYONE experienced anything like this??
Any and all input is appreciated..

 

[eevox]

Let's start with the basics.

Make sure all your wires on the alternator are clean and tight. Make sure your battery terminals are clean and tight.

What is the volt reading at the battery terminals with the truck off?
What is the volt reading at the battery terminals with the truck running? It should be 13.5-14.5 volts. (make sure you put your leads on the terminals themselves)

If you are getting that reading on start-up, let it run. You should see the voltage start to decline slowly. But it shouldn't go below around 13v.

Next, while the car is running, stress test the alternator. Put on your headlights, interior lights; if your radio is out, you might want to hook it up, turn on blinkers, AC. Then recheck the voltage with all this stuff running.

Check to make sure your serpentine belt isn't slipping.

I would trust the voltmeter over the instrument cluster gauge. If you say your voltage was falling according to your instrument cluster but then checked your battery, and it showed acceptable voltage, then the problem could be with your instrument cluster itself. The voltage gauge isn't really that accurate on these trucks.

 

[Dinnygee]

Let's start with the basics.

Make sure all your wires on the alternator are clean and tight. Make sure your battery terminals are clean and tight.

What is the volt reading at the battery terminals with the truck off?
What is the volt reading at the battery terminals with the truck running? It should be 13.5-14.5 volts. (make sure you put your leads on the terminals themselves)

If you are getting that reading on start-up, let it run. You should see the voltage start to decline slowly. But it shouldn't go below around 13v.

Next, while the car is running, stress test the alternator. Put on your headlights, interior lights; if your radio is out, you might want to hook it up, turn on blinkers, AC. Then recheck the voltage with all this stuff running.

Check to make sure your serpentine belt isn't slipping.

I would trust the voltmeter over the instrument cluster gauge. If you say your voltage was falling according to your instrument cluster but then checked your battery, and it showed acceptable voltage, then the problem could be with your instrument cluster itself. The voltage gauge isn't really that accurate on these trucks.

I cleaned the corrosion off the terminals pretty well, and they look shiny again!
When the truck is off, the battery stays the same voltage as it is when I shut it off.. (currently it's reading 11.89V)
When I turn the truck on it initially climbs around .01 to .02 volts, but starts dropping immediately after..
I'm reading the battery level with a digital multimeter, and I do put the prongs directly on the battery terminals.
I can confidently say the battery level is dropping around .01 volts EVERY minute and a half to two minutes, possibly faster.
When I stress test, the battery is drained at a faster rate too.
Everyone is saying it's a problem with my alternator but I've had it tested about 5 times in the last week and a half, and oreilleys says it bench tests great..
I noticed right away the voltage regulator on the alternator had a little bit of play in it though, so I replaced that today.. still no change.

Today I also went thru my fuse panel and started pulling almost everything that I could run the truck without.. juuuust to see if I could get my battery to level out and/or recharge, but again I was unsuccessful..

I'm feeling defeated

 

[eevox]

I cleaned the corrosion off the terminals pretty well, and they look shiny again!
When the truck is off, the battery stays the same voltage as it is when I shut it off.. (currently it's reading 11.89V)
When I turn the truck on it initially climbs around .01 to .02 volts, but starts dropping immediately after..
I'm reading the battery level with a digital multimeter, and I do put the prongs directly on the battery terminals.
I can confidently say the battery level is dropping around .01 volts EVERY minute and a half to two minutes, possibly faster.
When I stress test, the battery is drained at a faster rate too.
Everyone is saying it's a problem with my alternator but I've had it tested about 5 times in the last week and a half, and oreilleys says it bench tests great..
I noticed right away the voltage regulator on the alternator had a little bit of play in it though, so I replaced that today.. still no change.

Today I also went thru my fuse panel and started pulling almost everything that I could run the truck without.. juuuust to see if I could get my battery to level out and/or recharge, but again I was unsuccessful..

I'm feeling defeated

If you're only getting 11.89v, your battery is bad. But even with a bad battery, the voltage at your terminals with the engine running should be 13.5-14.5 volts because that's the voltage a good alternator puts out to charge a battery. If it's not, and you're sure the alternator is good, then it's a connection problem with your alternator.

It's not anything to do with your fuse panel, parasitic draws drain batteries when the car isn't running, so you can stop pulling fuses. With the truck running, you should read 13.5-14.5v at the battery.

A good car battery will have a minimum of 12.5v; closer to 13v is better. A good alternator will send 13.5v-14.5v to the battery when the engine is running.