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Old 06-08-2018, 11:37 AM   #26
88lowrider
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Join Date: Mar 2008
Location: Eugene Oregon
Posts: 121
Re: "Phantom" Parasitic Draw.

Quote:
Originally Posted by determined View Post
A few gremlins I have fixed on these over the years.

Cd player stuck trying to eject a disc, cycling over and over.

Power seat wiring and or switch sticking.

Power door lock actuator hanging up.

Engine and key off release alt belt, rotate pulley while holding the metal end of a screwdriver near the shaft coming out of the alternator and see if it suddenly becomes a magnet.

You mentioned puling fuses, did you also pull the tin resettable breakers?

A good laser thermometer can detect temp change in wiring drawing power.

Not hard to disconnect the computer to rule it out.

Disconnect harnesses one at a time to rule out a group at a time.
Still getting ready for the appraisal so I have had to put my attention elsewhere, And, I messed up.
I took the meter out and hooked the battery back up. Was checking it from time to time during the day, nothing, no draw.
Then it happened, the battery was pulled down and she would not start, pulled the battery cable off and the clip on the meter came off and lost power to the system, hooked it back up and no draw.....I missed it.

So, that won't happen again.

Radio was replaced and now on its own power switch.

No power seats but does have the power door locks and Yes, several years ago, found one that would stick. I was lucky and was able to find some NOS switches to replace them as they are hot all the time.

I have replaced and checked both the key switch and switch on the steering column under the dash. Check and set the adjustment rod.
I did Not test the Alt to see if turns into a magnet, just disconnected it, several times.

I did not pull all the fuses, just several at a time and no on the tin breakers. I was hoping to find the draw happening and start pulling.

I have the Fluke 62 Max + IR Thermometer which is pretty accurate but have not used it on the wiring, good idea, if I get it to start drawing.

This is the second computer since this problem has started. Last time I sent it to the fellow back east and had it rebuilt and tested.

The main harness for the engine compartment, I have not removed.

If I can just Catch it Drawing, I have a better chance on finding it of course. I have the hood light both door light switch's disabled so opening them to start testing and not cause any more draw.
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Old 06-08-2018, 12:27 PM   #27
88lowrider
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Location: Eugene Oregon
Posts: 121
Re: "Phantom" Parasitic Draw.

Quote:
Originally Posted by speedygonzales View Post
He swears something comes on by itself and draws a bunch of power but every time he looks at current draw it's gone.

He wanted to use something to record long term current draw. I told him to use a meter set to min/max.

He claims he can't find a meter that stays on for a long enough period of time.

I told him he won't have any such device doing a random power draw.

That's were it stands as of now.

Incidentally my Fluke 87 does NOT turn off during min/max mode. The auto OFF function is disabled during min/max operation.

Power-On Option: Disable Automatic Power-off
Automatic Power-off extends the life of the battery by
turning part of the meter off if neither the rotary switch
nor a pushbutton is operated for half an hour.
(Automatic Power-off is not allowed in the MIN MAX
Recording or Data Output modes.)
Not real sure now on why the amount that is drawing really means much other than anything over normal.

What I was trying to come up with is some device that once that draw started happening that it was trigger some sort of device, buzzer, something using its own power source to warn me when the draw is happening. Then I get in and start pulling and disconnecting things until I can find it.
This is obvious its not something simple but I need to at least try to narrow it down and try to isolate it.

Correct me if I am wrong. If it starts drawing and I can eliminate several circuits that will help narrow the possibilities of what is causing it.

My meters are that one Radio Shack meter (that one will stay on as much as two hours at time, never drops off in only 20 minutes) Its a manual/auto range dual-display digital multimeter with a PC Interface.
Then I have the Fluke 77 and the Fluke 336 Clamp meter. All are auto power down.

So, back to the triggering system. I am looking for something that once a draw starts happening, more than say normal, it will trigger a device that I can hear and come running. I have been chasing my tail on this now for some time as I have mentioned so all your help is More than appreciated !!!

I am back to the meter (radio shack one) is in line watching for amp draw, plus the Fluke 77 is under the hood to test the voltage.

One would think (at least this one) that a device that has its own power, put Inline that anything over a certain about of draw would have a buzzer or some sort of warning available ???

Thanks again guys for your help !!!! I am still at it.
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Old 06-08-2018, 02:07 PM   #28
speedygonzales
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Location: Smithfield, VA
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I'm sorry you don't really want help....you want someone to tell you you're correct.

You have had the wrong thinking since you started this adventure nearly 18 years ago. Now someone tells you a different approach and you diss the ideas. Why did you even come and ask the questions? Did you want vindication you were right? I've seen it hundreds of times. The OP puts up a question only wanting to hear a certain answer.

There is no mechanic in the US that will agree there is a random device that will come on by itself and put a large draw on the battery and shut off all by itself.

Where has nearly 20 years gotten you? Nowhere. I asked you several questions including the compressor and your meter fuses, you skipped right over.

Good luck with your search. I'm out of here.
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Old 06-08-2018, 02:41 PM   #29
88lowrider
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Join Date: Mar 2008
Location: Eugene Oregon
Posts: 121
Re: I'm sorry you don't really want help....you want someone to tell you you're corre

Quote:
Originally Posted by speedygonzales View Post
You have had the wrong thinking since you started this adventure nearly 18 years ago. Now someone tells you a different approach and you diss the ideas. Why did you even come and ask the questions? Did you want vindication you were right? I've seen it hundreds of times. The OP puts up a question only wanting to hear a certain answer.

There is no mechanic in the US that will agree there is a random device that will come on by itself and put a large draw on the battery and shut off all by itself.

Where has nearly 20 years gotten you? Nowhere. I asked you several questions including the compressor and your meter fuses, you skipped right over.

Good luck with your search. I'm out of here.
Sorry about missing the fuse in the meter, Yes, checked those, in fact the one meter I am using, I replaced it..
The compressor, no, its not bagged, just lowered so I do have air shocks on the back but manually full those.

Also sorry you were able to read that into this issue. Not looking for any validation or vindication whatsoever just stating the things I have done over the year..

Also I was Never able to see the brake lights on after walking back to the truck but they were off. All this means is I Thought I found it when I seen the brake lights come on that one day. So there was One device that would shut itself off after drawing, or was it for sure.?

Maybe I never really understood why trying to find what the peak draw was? It was still drawing amps, and bring down the volts so. I guess I will never know for sure, but hey, Thank you for all the information and suggestions.

I have dedicated Weeks at a time watching and trying different things, replacing things, testing them upon replacement just looking for something like a sticky switch (like the brake light coming on), door switches, ash tray and glove box lights, things that should be off with the ignition switch.

Nevertheless, its still doing it but I can't Catch it happening to find it. This last attempt I was on that thing for 6 days watching the battery voltage for any drop and nothing. Got busy walked away from it and 4 days later, battery too low to start it. (I also keep checking the draw on the battery to see if that changes, no it does not same draw)

So again, not sure you well ever see this but I want to thank you for all your help and suggestions that you have provided !!

Last edited by 88lowrider; 06-08-2018 at 02:46 PM.
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