Parasitic draw help

[squaredeal91]

Hey all, I'm working on a friend's 93 land landcrusher lol and they have owned it for years and has had a parasitic draw for a year or 2 now. Has newer AGM battery. In the past I've done some checking on it and it seems like the draw it had for keep alive items was acceptable however the battery would no longer start it if sat for 4 or 5 days approximately. Is it possible for a door open dome light switch could malfunction from moisture and cause a draw without turning on the light? It has the stupid toyota security system that is always using power but again hasn't been an issue in past years so something has changed. I want to test the battery away from vehicle to see if it drops on its own. Has aftermarket stereo and amp in it.
Any suggestions on what kinda results I should be seeing when testing battery after sitting for 12 or 24 hours? Maybe I should have the fancy Napa tester at it? Otherwise I'm going to be watching it with a multimeter to see if it has inconsistencies.

I'm a member on one of the Toyota sites and could have asked on there so Maybe im Barking up the wrong tree but I much prefer to stay on here with my people lol.
Thanks for looking.

 

[fast 99]

Install a test light in series with battery cable doesn't matter pos or negative. If it lights there is a draw. First thing to try removing fuses 1 at a time. Remember if door is open dome light may be on. If that doesn't help, unplug any aftermarket accessories. Make sure key is not in ignition.

There are other methods, but this requires the least equipment.

Can also use a digital meter the same way as a test light on AMP scale but do not exceed the internal fuse limit.

Normally I use a shunt with a MV digital meter. If you have those items I can elaborate.

 

[Snoots]

Sometimes, and I mean sometimes, aftermarket radios and especially amps, have a 'soft-start' which means the unless the amp is completely removed from the power supply they stay on a bit to prevent that 'POP' to your speakers when they turn on. It's worth checking.
Just my 2 cents.

 

[squaredeal91]

Put charger on this morning and it's done now. First test was the test light like @fast99 suggested and the light hyper flashes and I can hear a relay click in time with it somewhere under the dash. Now I'm going to try pulling fuses and stuff till i can make it stop then try to find the relay Itself and what it controls.

 

[squaredeal91]

Came to dome light fuse and it stopped hyper flashing. Now it will kinda quickly burn orange and die when I touch the light to it so I'd say I'm getting close now and have it down to this one circuit.

 

[squaredeal91]

Removed dome light fixtures and got it like this orangey glow With doors closes. That's why I'm removing and grounding switches.

 

[squaredeal91]

There's a separate map light by the rear view mirror that doesn't light up. I flipped the switch and now it doesn't overload and hyperflash. Now the light stays on solid. I'm removing all door open switches to ground them out as if closed. I'm hoping this answers something but I'm thinking other things are on this circuit. I'm searching for a diagram on this unless I can get a book soon.

 

[fast 99]

Mitchell online should have a diagram available that lists items on each circuit. It is a pay site. Many shops have access if you know a tech who will print it out.

 

[squaredeal91]

Found that there is a green light around the ignition lock cylinder that doesn't turn off and it's controlled by dome fuse. Grounded all doors and with green light out its zero on the meter. And .15 with green light in. Is this enough to kill the battery in a week? I'm sure other keep alive things are going but this light seems to be the culprit??

 

[Snoots]

Weird. But if you know where the ignition is, why put a light there? A question for the bean-counters at GM. IIWM, I'd leave it out.

 

[squaredeal91]

I'm going to leave the light out and put it back together and see if that makes the difference.

 

[fast 99]

That might be good, unsure. What I use for draws is a shunt. With a digital voltmeter set on millivolt scale should read less than .05 across the shunt.

First one that came up on the search there are others.

https://www.amazon.com/dp/B08FJF2L4W/

 

[squaredeal91]

I've got a diagram of sorts from toyota. Seems like besides dome light there's an automatic transmission combination meter in the dash I'm hoping to unhook it and make the test light quit burning/drawing power, Would also explain why speedo doesn't work and od light flickers on and off. I'm hoping to get it narrowed down more soon. I'm good with wiring repair but not so well with schematics and control modules. That shunt thing is pretty interesting.

 

[Jeff Lewis]

Took me years to figure out my clock was the draw.

 

[squaredeal91]

I found that with everything back hooked up like it should it will have an acceptable draw of .4 amps and had battery hooked up for 7 days and it started up but sounded a little slow cranking but not bad. Although it will still make a test light burn in-between battery and terminal but It goes out when I unplug aftermarket stereo for keep alive.

So in conclusion I'm pretty certain it's the radio and a combination of this battery getting only surface charges from numerous jump starts over the year and no actual good slow charge. As a result the battery wouldn't start the vehicle after a few days and sometimes overnight depending on how much it was driven to charge battery. When I started my work on this I did a 3 amp charge for 12 hours before I started. I'm hoping this all makes sense lol thanks for all the input!