Vanity: Battery drain on truck

3/22/2015 | me

[gundog]

I think his volt meter is in series from neg terminal to neg wire and he’s finding a drain of unknown amperage...not enough to blow a fuse, evidently. Seems like pulling fuses would isolate it to a circuit.

[waterhill]

Battery is new, alt is new. I am going look for an ammeter to borrow tomorrow night.

[PeaceBeWithYou]

Can you give the reason for using distilled water?

[MileHi]

3.Putting the meter in series parallel is not telling you anything aside from battery voltage.

For clarity

[rktman]

WHAT? You mean the fridge light supposedly goes off when you close the door?

[Steely Tom]

If I follow, wouldn't leaving his voltmeter in series and pulling fuses eventually get him there?

That would tell you something about the battery's state of charge, but it wouldn't tell you exactly which circuit is discharging the battery.

Of course some will want to argue about leakage currents and such.

But as long as you are going to go to trouble of creating a series connection, you might as well flip your multimeter to "A" and read amps instead of volts.

Just make sure you have put the probes into the "current" connections. Also make sure you've removed all rings and watches before having anything todo with an automotive battery.

[spokeshave]

I can’t think of a way to do it that does involve putting an ammeter in series with the battery and pulling fuses one at a time.

Don't need an Ampmeter.

just touch/scrape the wire on the battery terminal and see the spark....pull out one fuse at a time to locate the circuit.

If that doesn't work there is a short in the wiring somewhere..

Happened to me...eventually found a short in the wire leading to the rear upper cab light.

[Lx]

Ford’s usually have the starter solenoid on the firewall unlike lowly GMs which use the solenoid to make the electrical connection as well as shoot the Bendix out to the Flywheel teeth.

I don’t know how a 98 does it but usually, there’s a big cable that goes to the solenoid from the battery positive, this is for the starter. There’s another smaller cable on the positive battery terminal or on the battery side of the solenoid that powers the rest of the vehicle and also gets the charge voltage from the alternator. You could try to disconnect the positive from the alternator; maybe it has a shorted diode or something?

As someone else mentioned, you can also pull fuses until the draw goes away. Before EFI, you would start the engine and then pull the negative from the battery, if it died, the alternator was toasted, nowadays, that has the possibility of taking out the EFI which is no fun.
The radio has a parasitic draw to keep all of your pre-sets. How old is the battery? You would be amazed at what a bad battery presents as.
Let us know what you find?

[eastforker]

minerals in regular water will adhere to the plates and will weaken battery.

[Impala64ssa]

Try Glove box light (not shutting off when closed).
That's a possibility. When I first bought my 64 I left the trunk open when I parked it in the garage forgetting about the trunk light. A few days later it wouldn't start and the battery voltage was lower than Bruce Jenner's testosterone levels ;) Does the truck have an aftermarket radio/CD player in it? The clock in it should draw a very small amount of voltage from the battery when it's shut off, to maintain the time and station settings. Some of those cheap units, like those "$50 specials" from Wally World draw more voltage than they should, another thing I learned the hard way.

[gundog]

No pesky ionized molecules. Well, except OH- and H+.

[CGASMIA68]

minerals in water,city not great,worse well, will shorten the life of the bat.....crap builds up between plates quicker.

Not good

[gundog]

I see courtesy lights being mentioned. Any chance there’s a make-up light on a mirror, hidden by a visor? Seems a decent switch design would kill it, but....

[tacticalogic]

Any kind of electrical aftermarket accessories go to the top of the suspect list.

[Impala64ssa]

Ford’s usually have the starter solenoid on the firewall
Not any more, my wife's 2003 Ranger has it on the starter. It was one of Ford's better ideas, I remember when a friend of mine thought the starter in his 68 Torino GT crapped out I simply replaced the solenoid bolted to the inner wheel, end of problem.

[MileHi]

Nevermind. I thought he was reading across the batt terminals.

[FES0844]

I love how freepers help one another.

[VTenigma]

Main power relay may not be de-energizing, or bad diode in the alternator.

[tumblindice]

You could get a wiring diagram and inspect all the wires carefully for wear and a short, especially under/outside the truck, if she’s been using it as truck and not a fashion accessory.
But here’s the real redneck solution:
I have a `95 Merc. Sable and had the same problem. It has been a fine car otherwise.
The above was too much work so I just crushed all the bulbs I didn’t think I needed with pliers. Took about five minutes.

No more battery drainage and I drive the car pretty much in the daytime now. Have someone hold your beer ... I estimate its FMV by how much gas is in the tank, but it’s still my go-to sled.

[Nowhere Man]

A lot of the answers are good here but I like the clip ammeter idea where you place it around the negative battery cable to see if there is a huge draw. I worked for Advance Auto Parts for a few years and back in 2012, someone brought in a 1980 Cadillac and I checked it out and he was drawing 23 amps with everything off. I’d say there is a short somewhere, electrical problems can be tough. I once had a 1994 Ford Explorer where mu taillights didn’t work and the whole system needed rewired because they could not find where the short was. I was $800 poorer.