Weird Battery Drain

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Zitril

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Hello all, newbie here.
Firstly I want to say sorry for the long and sorta convoluted post, I am not really sure what is happening and mechanics have been unable to help.
I recently purchased a 2007 Expedition Eddie Bauer, it seems to have been a barn car (I actually found hay/straw tucked in many crevices). I replaced the battery because it was fairly old, and for the first month nothing seemed off, then I noticed the headlights flickering.
I took it into the shop and they replaced the alternator. It seemed good for a few days then I noticed on start-up in the morning that after about 30 seconds the battery indicator would flash in the notification area and then the battery-voltage meter on the dash would go all the way to high, then after 30 seconds it would drop back to normal. This would cause a bunch of codes in many different modules, and if I tried to drive within the first minute or so of starting the car, it would not shift down gears and get stuck in 3rd while moving. Re-starting the car at this point would clear all the problems. The codes are B1317 C2778 B1676 P0563 P0625. These all are electrical problems and I started looking around for possible causes. The first thing that I came across was possibly the sensor cable on the alternator. I checked the cable; it had good connection and connectivity through it. The next thing that I found could be a parasitic draw that drains the battery overnight and then while starting low, battery voltage causes the alternator to go high voltage. Just a thought by me.
When I tested the battery draw, upon first connecting, it draws a bit over 3 amps, then drops to about 1.4 amps, then finally drops to and plateaus at 0.2 amps of constant draw. I know draw is supposed to be between 20 to 50 milliamps (0.020 - 0.050 amps). I then went through and tested each fuse and found two interior fuses that affect the current draw. Fuse 5 (Keypad Illumination, 3rd Row Seat Enable, Brake Shift Interlock, SPDJB, TPMS initiators) and Fuse 25 (Demand lamps). Pulling Fuse 5 will drop the current draw down to 10 milliamps (0.01 amps) and removing Fuse 25 will drop the current draw to 140 milliamps (0.140 amps). I have checked the rear seats to see if they are still trying to move and they are not. There are also no lights or anything on while testing. If anyone has any ideas or thoughts, I am all ears. I don’t have a wiring diagram (yet) to better understand what is going on.

Thanks in advance,
Zitril
 
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Zitril

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I would also like to add the battery voltage meter only goes all the way to high about half the time, and when I have measured the voltage it is charging at 14.6v then after a while drops to 14.2v.
 

Adieu

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That's odd.

These things generally refuse to start far earlier than any battery indicator appears.
 
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Zitril

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I have never had it not start even when the voltage got down to 11.8 volts, though it has caused the whole electric system to restart (the radio/cd player to go through reset). So yeah it is very confusing.
 

Yupster Dog

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If anyone has any ideas or thoughts, I am all ears.

One thing it could be,
A lifted/intermittent ground could explain all your symptoms.
Do a VOLTAGE DROP TEST to check.
 
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Zitril

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One thing it could be,
A lifted/intermittent ground could explain all your symptoms.
Do a VOLTAGE DROP TEST to check.
I shall try that this weekend. Is there any reason why a drop test instead of ampmeter inline?
 

Trainmaster

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I agree with Yupster. Check your grounds. A known problem these truck have is a rear wiper that is seized and continually draws current trying to park itself.
 
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Zitril

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I agree with Yupster. Check your grounds. A known problem these truck have is a rear wiper that is seized and continually draws current trying to park itself.
I did check that and the rear wiper is free moving and does appear to return to proper park location. I will still re-double check the main grounds.
If it's been in the barn...and there's stuff tucked into crevices...just hope you don't have any chewed wires!
That was a thought I had but I have not found any chewed wires or anything at all chewed. This car confuses me so much. If anyone knows a good old school mechanic in the Washington DC DMV(Dc Maryland Virginia) area, let me know. And thank you for the responses. I really am just stumped.
 

Yupster Dog

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Is there any reason why a drop test instead of ampmeter inline?
2 different things. Look up voltage drop test you will see why.
Inline amp meter is only telling you how much is flowing thru it. A voltage drop test actually checks the cables that the voltage runs thru.

Put your meter to DC VOLTS Put positive lead on negative battery post (not cable clamp but actual battery post) then put negative on the chassis (make sure you getting good grounding point on chassis)
if you are getting anything above .03 something wrong with your ground.
Watch a video on voltage drop test and you can pinpoint down to the connection or wire that is bad.
It could even be just the battey post clamp, the voltage drop test will let you know the wires/connections are all good and you can move on to the next part of your diagnosis.
 
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