Jeep JL parasitic load... help...

[FulThrotl]

does anyone know what the parasitic electrical load on a Jeep JL is?
there is a lot of bells and whistles, but i'm guessing the continuous load
is between 5~10 watts.

not counting any aux stuff, just the ECU, in dash stuff, and computers.

i've got a good clamp on wattmeter, that i know is accurate, and the
jeep is pulling 58 watts, with everything powered off, and timed out.

before i go on an easter egg hunt, it'd be nice to know what normal is.

thanks

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[garyji]

I'm totally just guessing, but 58 sounds crazy high.

G.

 

[FulThrotl]

well, it's sitting at the curb, the hood switched are weighed down by the tool roll,
the ipad on the dash us unplugged, as is the dash cam. wattage has dropped from
60 to 55. the key fob is in the back bedroom, so it won't wake anything up, and
the wattage moved down to 55.

i'll give it an hour to go to sleep, and see what the wattage is.
all aux. loads are running off an sPod on the aux battery, as is
the 3KW full sine inverter, which has a load turned off, of 3 watts.

let's see if it goes down any. no motions, jiggling, fobs nearby, nothing.

 

[roaniecowpony]

 

[FulThrotl]

even more interesting, i went out without a fob, to sneak up on it, and
when i get up and look at the meter, it's 42 watts, and within half a second,
it bumps up to 52 watts. and i'm not physically touching anything.

it's done it three times in a row. 42~52. at first i thought it was a fluke,
but it's perfectly consistent.

when you use the fob to unlock the doors, it spikes at 150 watts for a second
as the solenoids operate. then back down to 52 watts. makes sense.

i fucking hate chrysler. this thing is nothing but a fucking dodge minivan
with lockers. fucking piece of shit.

simple vehicle maintenance should be easier than an apollo 13 rescue,
or hostage negotiations with a terrorist.

 

[JJMalone]

Nah, trying to measure low power and low current DC is tricky with a clampon. Breaking the circuit and putting an ammeter in series will be way more accurate. I would believe up to 50 milliamps. Sure you zeroed your meter? A 5 amp drain would kill the batteries overnight.

 

[FulThrotl]

Nah, trying to measure low power and low current DC is tricky with a clampon. Breaking the circuit and putting an ammeter in series will be way more accurate. I would believe up to 50 milliamps. Sure you zeroed your meter? A 5 amp drain would kill the batteries overnight.

the meter is zeroed. it zeroes when powered on.
i also has a Oscope built into it, and will calculate
a bunch of data. harmonics, THD, phase angle,
power factor, etc. the thing is stupid accurate, and
will resolve within a couple watts, irregardless of voltage.
new, they are currently $3,000. it's not the meter.

and, the current flow is killing the battery overnight.

my original post was to see if anyone had a realistic number for a JL.
i'd figure less than 0.7 amps, max. it is running about 4.5 amps,
and that seems like it would kill a battery overnight, which it is doing nicely.

i just wanted to find a benchmark to aim for, before i ripped everything
apart, pulling fuses and swearing, both of which i can do well. i've been
an electrical contractor specializing in control systems and robotics for 42 years.

i can swear logarithmically, and exponentially, if need be.

i'm just looking for a realistic baseline.

 

[BDinTX]

Apologies for not answering your question but if you’re looking for a way to track down where the draw is, this method looks pretty good.

 

[FulThrotl]

Apologies for not answering your question but if you’re looking for a way to track down where the draw is, this method looks pretty good.

that is cool. i'd a never thought to look for parallel tables for automotive.
they exist in public utility land, and it's a way they measure current and
potential for public utilities at voltages of 240,000 volts, and current in
thousands of amps at those voltages. PT's and CT's are used.

this won't be that accurate, but it'll be good enough. you don't need a
CC measurement of the volume of the hole in the tire leaking when you put it in the water
tank. you just need to know where the bubbles are at.

thanks again for your help.

 

[BDinTX]

Hopefully it helps you zero in on the problem area quickly. Keep us posted!

 

[Slate]

the meter is zeroed. it zeroes when powered on.
i also has a Oscope built into it, and will calculate
a bunch of data. harmonics, THD, phase angle,
power factor, etc. the thing is stupid accurate, and
will resolve within a couple watts, irregardless of voltage.
new, they are currently $3,000. it's not the meter.

and, the current flow is killing the battery overnight.

my original post was to see if anyone had a realistic number for a JL.
i'd figure less than 0.7 amps, max. it is running about 4.5 amps,
and that seems like it would kill a battery overnight, which it is doing nicely.

i just wanted to find a benchmark to aim for, before i ripped everything
apart, pulling fuses and swearing, both of which i can do well. i've been
an electrical contractor specializing in control systems and robotics for 42 years.

i can swear logarithmically, and exponentially, if need be.

i'm just looking for a realistic baseline.

Did you ever get an answer? I am trying to troubleshoot this myself. I got .55, but not sure if that is above or below baseline.

 

[BuffaloBill]

I’d second the idea to measure current draw using an ammeter. Is that what you used to obtain the 4.5A reading? Just to confirm the $3000 Fluke‘s clamp-on reading, etc. It’s not a given that a dc clamp-on’s reading is spot-on, even one that costs a lot.

I notice now this thread is from last year! I too am curious how it turned out.

 

[FulThrotl]

Did you ever get an answer? I am trying to troubleshoot this myself. I got .55, but not sure if that is above or below baseline.

the jeep is now running a 300 AH lithium battery in the back, to drive the 3kw inverter.
it has a higher float voltage than the oddesy group 25's under the hood. there is a DC
power 340 amp alternator on the engine. the lithium in back has it's own battery
management stuff built in, and a 200 amp charge and discharge rate.

so the lithium charges to 100% fast, and when turned off, dumps about 3 amps to trickle
charge the under hood batteries, keeping them both paired and topped off. after a
week, the lithium drops to the point it quits topping off the batteries under the hood.

the thing gets driven every week, usually more than once. the problem stopped being a
problem. it's ok. jeeps have other things to go wrong. FCA largely sucks.

does it still have parasitic drain? i'm sure it does, intermittently.

the jeep had the oil cooler housing replaced at 120k, along with every other thing that
might go south. at 125k, it blew a head gasket. i picked up a whole new engine, a tear
out from a hemi upfitter, not even broken in, for $3k, delivered.

so, it's got a fresh engine. coming back from central nevada last week, my wife asked
"so what would selling this and getting a G wagon look like."

it probably would look good, if you like dragging that much money thru the rocks.

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