Battery drain

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A major source of a battery drain is the alternator having a shorted output diode. This circuit isn't fused, so pulling every fuse that you have looking for the drain will not help. With the ignition off, disconnect the alternator output wire and put a voltmeter between the wire and the alternator terminal. Voltage should show zero or very close to it.
Danny, There is a learning curve to all this, lol. Plus it is cold out and I have no garage. But I hope to attempt this soon/someday. Other than adding fluids and checking fluid levels, the only thing I've ever done on a vehicle is change a tire and change the oil. Decades ago. Thank you:)
 
You did not mention how fast your battery goes flat. That will indicate what kind of accessory circuits to look at first. You’ll likely need a multimeter, but if the battery goes down fast a test light might do the job.

***Multimeters are not that hard to use. They cost around $30 and can quickly tell you if your battery is charge up or if your alternator is charging it. It’s a pretty good tool to keep around.

It drains overnight, in all kinds of weather.

I will buy a multi-meter. Thank you for such a thorough explanation! I appreciate it.

Last night I read that the most common drain is from aftermarket parts/products improperly installed (Ie. backup cameras). I removed the face plate from the bluetooth radio, hoping that is the culprit. Also read that I should try to remember when the problem started and if I added something new at the time. I'm starting to think the truck had the drain when I bought it.
 
I can't help with fords, but on chevy's I have had battery's go dead from starters, and radios. note chevy stock radios were the most common problem. harbor frieght tools sales a fuse adapter that will tell you the amp draw for any fuse when the tool is installed in the fuse location. this tool found a short in my A/C compressor circuit. that a shop could not find. quite a few shops like autozone will test your battery and starting circuits, and your charging system for free. if your battery terminals are loose and or dirty clean them. for a loose connection use a sanded 1 inch wide strip of aluminum can, sanded clean then wrap around the post and reinstall them.
 
Thanks Denny... now that is the easy way to find an electrical problem on a vehicle.

It's called a 30 Amp Automotive Fuse Circuit Tester..... $15 at Harbor Freight Tools.
 
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Bad diodes in the alternator will drain the battery. Not sure if that is still an issue with modern computer controlled alternators but it used to be pretty common.
 
Danny, There is a learning curve to all this, lol. Plus it is cold out and I have no garage. But I hope to attempt this soon/someday. Other than adding fluids and checking fluid levels, the only thing I've ever done on a vehicle is change a tire and change the oil. Decades ago. Thank you:)
OK, until you find the problem then, get and install a battery disconnect. When not using the vehicle, just disconnect the battery. This device will also help when testing the alternator.
The terminal on the alternator will always have power, so if the wrench that you use to take off the nut touches anything that has a metal ground, you will have a direct short if the battery is connected.
Disconnect the battery, (one way or another), Then take off the output wire from the alternator, Attach the voltmeter, (put it on DC Volts), and reattach the battery. If the meter shows voltage, there will be current flow when the wire is attached. The higher the voltage it shows, the larger the drain. When putting the wire back on the alternator disconnect the battery again just in case the wrench hits metal again.
 
I think something is draining the battery on my 1995 F250. I'm nervous about it being an expensive repair job (to find out what is draining it). I just got the truck out of the repair shop and the bill was almost $1,400.00. Tonight the truck wouldn't start and it has a brand new battery. I used a fully charged jumper pack on it and it seemed like the truck/battery was sucking the power down when I tried to start it. Still wouldn't start with the jump pack. It was only 20 degrees out. Yesterday it was minus 20 wind chill and I never started it.

I've been having an electrical problem for a long time and a mechanic told me I should take it to a shop that specializes in electrical issues. He gave me two names. But then I let my son -in-law borrow the truck and he blew out the transmission plug. After that the truck had no power on hills. Eventually died on a hill and wouldn't restart with a jump (when my daughter borrowed it).

I had it towed to a transmission shop. Hence the $1400.00 bill. The transmission was fine, but he did fix many things that needed attention. Just not this electrical issue. (I was convinced the transmission had issues and forgot what that other mechanic had told me). The transmission shop spent most of the labor hours on a bundle of wires that were "cut". I suspect it was chipmunks, because I saw them repeatedly climbing up my truck tires.

Without this issue I could sell the truck and break even (because of the demand for used vehicles). But I'm worried this electrical issue will be very expensive.
Has anyone had this problem? I Googled it and it's called a "parasitic draw". What I want to know is if it usually ends up being an expensive fix. Probably nobody can answer that without diagnosing the truck or completing the job. Just super disappointing. I was planning on buying a used topper and leaving around February 5.

Thanks (for letting me vent, if nothing else:).


Karla, watch the video and follow the step to find the parasitic draw. You can get a voltmeter for very cheap or even likely borrow one. It could be something more complicated, but this should at least get you in the right ballpark to start looking for the problem. Its a 95, so the wiring isn't gonna be that bad. You can do it!
 
Many thanks to everyone for the suggestions and instructions. Last night I removed the face plate to the bluetooth stereo that came with the truck and this morning the truck started. I doubt that was the issue, but we can hope! Once it warms up I will attempt the different things everyone suggested. On the 5th I'm driving 400+ miles south to visit one of my kids. Between my daughter and I, we'll figure it out. I hope:)
 
The thing about electricity is that when it flows it generates heat.
To find AC freon leaks you use dye and a UV light.

If the drain is enough to flow about 500mA or more.....
Likewise, you could find that electrical drain with an Infra red camera like a SEEK Thermal or FLIR etc.

The wires and components carrying the drain would glow and stand out.

also - You mentioned you had odd alarm system problems.
I can't say for sur with your vehicle, but I can't tell you how many vehicles have small water leaks under the dash affecting the BCM or fuse panels causing drains, shorts and all kinds of mystery electrical problems.
 
I think something is draining the battery on my 1995 F250. I'm nervous about it being an expensive repair job (to find out what is draining it). I just got the truck out of the repair shop and the bill was almost $1,400.00. Tonight the truck wouldn't start and it has a brand new battery. I used a fully charged jumper pack on it and it seemed like the truck/battery was sucking the power down when I tried to start it. Still wouldn't start with the jump pack. It was only 20 degrees out. Yesterday it was minus 20 wind chill and I never started it.

I've been having an electrical problem for a long time and a mechanic told me I should take it to a shop that specializes in electrical issues. He gave me two names. But then I let my son -in-law borrow the truck and he blew out the transmission plug. After that the truck had no power on hills. Eventually died on a hill and wouldn't restart with a jump (when my daughter borrowed it).

I had it towed to a transmission shop. Hence the $1400.00 bill. The transmission was fine, but he did fix many things that needed attention. Just not this electrical issue. (I was convinced the transmission had issues and forgot what that other mechanic had told me). The transmission shop spent most of the labor hours on a bundle of wires that were "cut". I suspect it was chipmunks, because I saw them repeatedly climbing up my truck tires.

Without this issue I could sell the truck and break even (because of the demand for used vehicles). But I'm worried this electrical issue will be very expensive.
Has anyone had this problem? I Googled it and it's called a "parasitic draw". What I want to know is if it usually ends up being an expensive fix. Probably nobody can answer that without diagnosing the truck or completing the job. Just super disappointing. I was planning on buying a used topper and leaving around February 5.

Thanks (for letting me vent, if nothing else:).
Start with a fully charged battery. Disconnect a battery cable at battery. In the dark, tap the cable on the battery, if there is a spark, you are right, there is a parasitic draw within the vehicle. If no spark, then it will likely be the battery. Next disconnect the alternator, again tap the battery cable and see if there is a spark, if there is, that will rule out shorted diodes in the alternator and point elsewhere. Some times I have seen the window wiper parking relay will be stuck closed, unplug the wires going to the wiper motor, check for a spark again. if no spark then you have found it.
Otherwise any wire that has broken insulation and touching a metal part can cause a drain, It is possible that the the key switch is not turning everything off, replace the switch if in doubt. Since it is cold weather where you are, disconnect the battery and keep the battery charged so it does not freeze. Ice inside the battery will damage the inside of the battery and likely cause an internal short which means the battery is junk. From your description of your trouble and the weather, it may already be too late, you can't know until you charge the battery with one cable unhooked , then check the battery after several hours of standing idle with a load tester available at most any automotive store for cheap or on amazon. It would be a good idea to get a cheap volt/ohm meter, less than $10 bucks . If you can get a real jump from another vehicle enough to get the engine running, then check at the battery for around 13.5 volts, even near 14 volts with the engine running just in case the alternator has failed.
Some of the older fords had an external regulator bolted to the fender well under the hood which have been known to loose ground due to rust at the mounting bolts, remove the bolts and clean the area till you get bright metal. Simple tools and a lot of patience go a long way to sort out electrical issues, Cold weather makes the task hard on hands and patience.
Ken
 
A DC ammeter that accurately reads even low value dc loads that clamps around a battery cable or smaller wire is my favorite tool for battery drains. Some meters have the function built in, and there are separate clamp types that plug into a multimeter you already own, usually by selecting or using the DC millivolt range (converts amps to millivolts). No need to disconnect the battery.

Clamped around a battery cable, it shows amps leaving the battery. Removing fuses to see if it goes away helps. Clamped around the big wire to the alternator, will show drain there. On your year range Ford, IIRC, there is always about a 75 milliamp/.075A) drain.

When shopping for a DC clamp-on meter, online sellers make it confusing about whether it will actually read DC amps. Shopping for the separate clamp-on accessory is less confusing. Measuring DC amps is as important as measuring volts.

The failure of the jump starter pack was probably due to trying to charge the dead battery along with starter amps. Removing the negative cable, attaching the jump starter, cranking and then quickly reattaching the negative cable often works.
 
Sorry for not replying to the newest posts. I'm overwhelmed. I know nothing about engines and I can't afford to pay a mechanic again. Not sure what to do with this beast of a truck, but I want to thank everyone for the help.
 
It drains overnight, in all kinds of weather.

I will buy a multi-meter. Thank you for such a thorough explanation! I appreciate it.

Last night I read that the most common drain is from aftermarket parts/products improperly installed (Ie. backup cameras). I removed the face plate from the bluetooth radio, hoping that is the culprit. Also read that I should try to remember when the problem started and if I added something new at the time. I'm starting to think the truck had the drain when I bought it.
Some of those radios will have 2 positive leads. One goes to the battery to keep the memory alive and the other goes the switch so it doesnt drain the battery.
 
So removing the face plate wouldn't help eliminate the radio as the culprit? The wires wouldn't come from the face plate anyway. Duh:D Ugh.

Thanks Freelander
 
So removing the face plate wouldn't help eliminate the radio as the culprit? The wires wouldn't come from the face plate anyway. Duh:D Ugh.

Thanks Freelander
I fixed this same problem years ago, some kid bought a new radio for his car and told his momma he knew how to install it, will after the battery went dead a few time, he brought to me. Luckily he still had the wiring diagram for the radio and I figured out was wrong real quick.
 
The Sony booklet and remote for the stereo came with the truck:) Maybe the wiring diagram is in the book. I have to get to warmer weather before attempting to tackle this. 17 inches of snow expected tonight.

Thanks.
 
When I bought a used Ford Transit van, after leaving the van sitting only a week or two, the engine wouldn't start and I discovered the battery had drained. Long story short, it turned out when I went to the Ford Transit forum, it's a known issue that Ford Transits have, that if you don't drive the vehicle regularly, the battery drains due to a draw occurring when the engine is off. I'm thinking maybe you might have a similar issue?

An incredibly dumb engineering mistake but what can we do.

I installed a battery disconnect switch to prevent this and also function as a theft prevention device. No problems since.
 
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