Use a voltmeter between the negative battery post and the negative cable, see what kind of draw you have and start pulling fuses. This way you don't have to worry about what setting to have your amp gauge set at. The old primitive sweep voltmeter works just fine.
And just my two cent's worth, your battery should not go dead in a 7 mile trip, stock alternator should be fine, you have a excessive voltage draw on something. My wife drives our E250 conversion van to work 3 miles, both heaters blazing, lights on, been cold as ever this year, die hard is three years old, sometimes it will sit for long periods of time, always starts.

 

I agree with the problem not being the alternator, or the battery. if i take my son to school, (an additional 1.2 miles), i have no problem, if i dont take him to school, i have problems. I am going to try with a voltmeter again this weekend, and hopefully can replicate the problem.

 

A just for giggles diagnostic test, try this on each of the different days. Charge the battery up before you leave. Drive your short distances and when you get home, hook the charger back up. If the charging system is working correctly, it should take close to the same amount of time to recharge the battery.

Even if this doesn't show a charging system issue, you will have verified the alt working nicely and you will have a charged battery to check the draw.

If you want to verify your battery is working correctly. Disconnect it from the truck, charge it up and meter the voltage once the charger has finished. Let it sit over night in the cold. In the morning, check the voltage again. The voltage should not drop overnight without a draw.

I know no one thinks these are the issues, but thinking and knowing are two different aspects. Plus a failing battery can create all kinds of issues that are hard to diagnose, the more information you have, the further along you can work.

 

battery is not the issue. 4 batteries later, and problem reoccurs only in the winter time. heater fan, defroster, headlights not the issue, as i have run without all of them and still had the problem.

 

13 Volts seems a bit low, yes some would disagree, but it depends on your alternator. Is this with only main excesseries running (I.E. lights off). All of mine runs 14 to 14.5 with only main excesseries, 12.5 to 13 with all lights included. Anyhoo, sounds to me like you have a "jumping ground to short GOSTING problem". What I mean by this, it is normally in your lights wiring. Under different car vibrations the wire will touch, when not vibrating (different levels of) all is good (no draw from battery). I put up with mine for 4 years, finally I pulled the harness out and inspected. Low and behold shorted tail light hot wire to the frame of the car. Mine started out the same as you are saying with your car, then I had to unhook the hot wire to drive without draining the battery, then leaving the hot wire hooked up while not running killed the battery. Now I start mine well below zero with a turn of the key.

 

From experience I have went back and forth with the battery to the alternator, even put on a one wire alternator still had the very issue you are having. Not saying it couldn't be the type of battery, but normally it is a short to ground. 13 volts is fine, but remember that has nothing to do with anything when there is a short to ground, especially when it's in the light wiring. I had to unhook my positive post every time I started the car to keep the battery from going dead. Then it got worse, battery would even die with car shut off. It was intermittent until the bare hot wire seared to the frame, therefore causing a constant draw at all times unless the battery was unhooked. Yes my volt gauge still read 13.5 with lights to 14.5 no lights (on one wire alt now). Take a volt meter, pull your light bulbs one at a time, both wire contacts should not read the same (hence a short to ground). I have helped many people with this, import, domestic, doesn't matter. The systems may be more complex, but in the end are designed to operate the same (down to wiring system grounds versu hot). Good luck, chime back if you have any questions, I am bouncing all the forum since haven't figured the workings of it.

 

hey I have tried to send you some helpful hints, but I don't see where I have answered you, new to sight, but want to help. Can you some how tell me if my suggestions are coming through to you? User eddiec1969-02

 

I agree with the battery check. A person can beat themselves up trying to figure out a draw when it is only a bad battery cell, in particular to cold weather. But, if you have replaced it, then please do the bulb connection check with the volt meter. I have seen this problem in my own and friends vehicles. When you do it, the vehicle doesn't have to be running, just have the battery hooked up and your volt meter on ohms, not diode test (buzzing). You are not looking for contanuity, with a short to ground everything will appear to be normal across the meter (ohms only). WATCH the numbers. Some will be high on your engine compartment due to diodes which prevent bleeding back from the charging system. Say you have 2 connections in a light bulb, there is always a chassis ground in the system, therefore, when you hold red lead to a connections, black to ground, then go to the second connection they should not be reading the same or "close too".

 

Have you gone out on those cold nights to make sure none of the interior lights are on? That has usually been it in my experience. Especially with the underhood lamp. Those things are pretty bad about coming on and staying on when it's real cold. Door switches don't like being cold and wet either.

I'd pull the bulbs and see if your problem goes away. It only takes one of them on on a cold night to kill a battery.

Also if you are buying cheap batteries like the last car lot I worked at did then stop and buy a good one. Personally I use optimas. I've got 5 of them in my F-350. 3 are for the slide in that I keep on it. I also have 2 big solar panels on the roof that charge all 5 batteries. They make enough juice to run the heater, fridge and all the lights for as long as I want. If any of my batteries ever go dead with those panels then something is really wrong. I do have the two truck batteries under the hood on a low voltage disconnect just in case though.

Anyway, Pull those light bulbs for a while and see if your battery goes dead. The only other cause I can think of is a bad voltage regulator. They can do all kinds of weird things. I've also run into the wire for the dome light, the hot one to the door switch, being pierced by a screw before. That should be popping fuses though.

 

ReAX is giving good advice. The batteries are going dead because of high quiescent load with key switch off, or a high resistance short to ground. This is the only explanation for sudden discharge of the batteries. Either way, you need to find the offending circuit and eliminate the current draw when the key switch is off. You've killed enough batteries to know this is the problem.

If I were in your position, I would be searching for a high resistance short to ground. In other words, there is a wire that is shorting to ground somewhere but it's not a severe short that throws sparks and blows fuses. It's just a slight nick in the wire, or burnt coils in a motor that is grounding out. It could very well be intermittent and be made acute by cold weather.

The only way to whip this problem is to measure current draw at the batteries and start pulling fuses to find which circuit has the problem. Once you find the circuit you need to hunt down the problem on that circuit. You will need to measure very small electrical current so you need a device that is sensitive enough to measure a fraction of an amp. Nearly any digital multimeter with a "mA" setting and 10A fuse will do the trick.

1. With key switch off, disconnect either battery (+) terminal or battery (-) terminal, whichever is easiest. Make sure you remove all cables to that battery terminal. Wrap the ends of the cables with a towel so they don't accidently touch metal on the truck.

2. Use the multimeter to complete the circuit again by connecting one lead to the empty battery terminal and the other lead to the loose battery cables. With the multimeter in "mA" mode the display will be showing milliamps of current. Allow 30 seconds for electrical devices to go through start up procedures and the current reading stabilize.

3. If the reading is under 50 mA then you haven't got the test conditions right. You need to try to recreate the problem somehow until the current reading goes up by a substantial amount.

4. Assuming you see a high current draw, begin pulling fuses until you find the major offender. Some fuses may result in slight decrease of current. Ignore those. You're hunting for the problem child.

5. After you find the circuit you will then have to hunt through the entire circuit to find the problem. Begin by checking the easy stuff, like electrical devices. If you don't find the problem then you will have to hand check all the wiring on that circuit for nicks or damage any place it makes contact with truck sheet metal.

This is not a fun task and might be extremely frustrating. If this isn't something you want to do on your own, then at least find the offending circuit so you can instruct the shop where to look. Seems that prior efforts by the dealer were either insufficient, or the problem wasn't happening at that time.

 

Actually, questions were asked and you didn't have any answers. Just attacked another member. Knowledge is only useful if you apply it for some benefit.

There are some really smart people at this site that deserve your respect. You're not going to fair well with a cocky attitude. Because you never know.... one of us might also make a living as a professional engineer working on everything to do with starting and charging systems.

 

Read through the whole thread, and can only say there are some good points in here and some bad points also...including at least one no no! I'm not gonna point out any single post, just caution the OP to read everything with a grain of salt, and if it doesn't sound right, don't do it. (JMHO).


“The problem with Socialism is that you eventually run out of other people’s money.” Margaret Thatcher

 

Some day this thread will come up in a search. Pointing out the "no no" might save that person some expensive trouble.

If I was a betting man I'd say you are thinking about running the vehicle batteryless.

 

I had a similar experience this winter where my voltmeter showed plenty of battery voltage but my new batteries went dead on me at work. Did a bunch of testing on the charging circuit and wiring to no results. Finally took my 110 amp alternator to my local automotive electrical expert and found that the alternator had a bad diode that would work or not depending on the temperature. Had new diodes put in and all is well. Only cost me $60.00 in total repairs. If I may suggest, take the alternator to a good repair shop and have it load tested. My 2cents worth of advice.

 

Actually I missed that one, and you are right- pointing out a no no could save someone some trouble. Try these:

"Test light only works with a certain range of currents. Too little current and it won't light, but still could be a draw. Too much current and you'll blow the bulb".


"Use a voltmeter between the negative battery post and the negative cable, see what kind of draw you have...".

".....just have the battery hooked up and your volt meter on ohms, not diode test (buzzing)".

Make what you will of these .........



It has been said that politics is the second oldest profession. I have learned that it bears a striking resemblance to the first.’ -Ronald Reagan