Problem With Power Outlet

By "jump post" I assume you don't mean the battery post. If not, then I'm
not sure what you're referring to.

 

Uh, I'd probably compare it to something like 12V, since this is after
all a 12V system. Now if I was checking an outlet in my house I'd
probably check it against oh, say, 120V. If I was testing something
powered a 9V transistor battery, I might test it against something like
9V. Are you catching on yet?

Now, if you tell me that the nominal voltage of the power source is not
known, then I would test the power source first, but that simply isn't
the case in a car or most other electrical and electronic devices.


Matt

 

I never said a lead acid battery should have a cell voltage of 2.2V.
Now it is my turn ... I defy you to find where I said that.

Now, are you going to comment about both Bill and me pointing out your lie?


Matt

 

Hi...

Ouch, you guys are making the old retired electrical guy's head
hurt

In this case, check what's available at what you're calling a port;
compare it to what's expected - in this case 12(ish) volts.

If you don't find what you expect, then work your way backward from
there.

Hey, when I flip the kitchen light switch and it stays dark, I
shouldn't book a flight to Niagara Falls, right?

And in addition, seems to me that you're all overlooking the OP's
original comment that the invertor beeped before shutting down.
Methinks there's a really important clue there

Take care.

Ken

 

When the engine is running, the

I'm totally ignorant about these things, and I shouldn't jump in here. But I
just want to state that I don't think that what I wrote above necessarily
indicates a battery problem. When the engine's on, there is more power due
to the alternator. No one disputes that. So if the lines aren't providing
enough power to the power outlet, then the inverter might work fine with the
engine/alternator on, but still be much lower than it should be (but enough
to keep the inverter running); whereas when the engine is off and the power
is naturally less, it's below the threshold that the inverter accepts. Thus,
the problem could be that the outlets aren't getting enough power, but are
getting at least the minimal with the engine on, though they should be
getting more.

That being said, the voltage readings I just posted seem to discount that.
However, I just wanted to point out that the problem only manifests itself
with the engine off doesn't mean that the problem doesn't exist with the
engine on, although perhaps not manifested.

Neil

 

And a new battery, which at three years on a factory battery, isn't a bad

Ever have a late model Mopar battery? Ever consider that 9 years is 4 over
the average life of the best lead acid battery life expectancy on the
market?

If he can't operate a VM, maybe his best option is a shop.

My suggestions were:

1) test battery voltage
2) test port voltage as comparison
3) act accordingly.

All easily done on his own if he learns to operate a VM.


--
Max

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)

 

Ken, you are a genius! Check against what is expected. What a concept.
Max, are you listening?

Matt

 

What happened to the battery load test? That used to be a first
suggestion. Your technique is getting better. Swap 1 and 2 above and
you'll be there!

Matt

 

No, I would check the voltage at the power outlet first. Then I would

Given that the battery is 3 years old and a factory battery, and that it
read 12.6 just after being in a charge cycle, AND that 2.2v per cell is .6
more volts than were found, confirmation of battery condition is well within
reason. Second, since the test of the port was not within moments of the
battery voltage test, the battery will need to be retested at the same time
testing of the port is done so an accurate comparison may be done.

Typical reply of someone who doesn't take into account ambient temp, rest
time of battery, charge cycle voltage, age of the battery, condition of the
battery, and quality of construction of the battery.

Testing battery voltage inorder to compare it to the port voltage is
essential. Proper training says do it first, but when only two things need
to be tested, doing it second will suffice.... but it MUST be done.
--
Max

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)

 

Yes, it has been in the Batt position since I bought the car last week, and
the back power outlet works without the key. However, the front one still
requires a key. Any suggestions on how to get that one to be on all the
time? (Not that it's relevant to this discussion, but it would be good to
know, if it were possible.)

The service manager at the Dodge dealer said that Dodge starting disabling
the always-on setting for the front power outlet, even with the fuse in the
Batt position, because of people leaving their cell phone chargers plugged
into the front and it starting fires in the front carpeting.

Neil

 

Digital doesn't matter, but red is posotive(center) and black in
negative (ground - outer)

 

Except that the normal cell voltage for a lead acid battery is 2-2.1 and

Better tell that to your "expert" buddies.

I'll restate for clarity.... 12.6 isn't optimum for a freshly charged
battery. Comparison to battery voltage is the only way to tell if the port
is lower than it should be for proper operation. Comparison of port voltage
while engine is off and inverter is operating to battery voltage under the
same conditions is the only way to find if the voltage drop is caused by
inverter operation.

If any of the above is left out, the diagnostics will not accurately reflect
the problem, and you might as will be replacing parts in hope of a cure.


--
Max

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)

 

It's referred to as a trasconductance tester - I guess to be perfectly
accurate its a conductance tester.
Regardless, it works.

 

Don't forget you need a different voltmeter to read AC and a different one
to read DC...

Don't laugh, someone somewhere would buy them.

Ted

 

MAX and others!

Doesen't ANYONE who is posting to this thread have a 2003 Caravan that they
could spend a few minutes with a DVM to make some measurements with to
give the OP something for comparisons sake?

Ted

 

Max, this is completely stupid. If the OP was going to do the shotgun
approach a much better way than screwing with the battery would be
to simply go to an electronics store and buy a different brand of inverter
that didn't have such a sensitive low voltage detection circuit. Why go
to a shop at all?

Frankly in my humble opinion auto electronics should operate in a voltage
range from 9v-16v as an auto electrical system is probably one of the more
hostile power systems you can find.

Ted

 

Matt, your absolutely right, a battery load tester is a big waste of money
for
automotive troubleshooting. A battery load tester is a great thing if what
your doing is preventative maintainence on a rack of 10 sealed lead-acid
gell
cells for some 15K watt large UPS, and each battery costs $80, and all
they do is sit there on a charger 24 hours a day. But for automotive
testing, the headlights and starter provide plenty of load for testing, all
you really
need is a volt meter and a battery hydrometer.

Ted

 

Unfortunately, those testers also miss batteries that have a high rate
of self-discharge for some reason or another. My wife had one of
these once, a Sears Diehard. I could disconnect the negative battery
lead and 2 days later the battery couldn't start the car. Sears refused
to replace it under warranty. That was the last Diehard I ever bought.

Ted

 

You would have to rewire the front one to make it hot all the time

 

Except that 2.2V per cell isn't correct.

Typical answer of someone advocating expensive tests before inexpensive
tests. You must run a garage.

If the power outlet tests 12.6V or higher open circuit and 11V or
greater under load at the outlet, why do you need to test the battery?
Why MUST the battery be tested? I'd be testing the inverter at that
point...


Matt