Parasitic draw (power draw) issue. Help!

Ripper238

Senior Member
So I have been having a pretty heavy Parasitic draw of about 180mA where it should only be ~50mA when the 4R is off. We pulled all aftermarket electronics and when i remove the Short pin fuse under the hood that conserves power when in transport it goes away. Think its the ECM/BCM/ECU (Not sure the terminology) when that fuse is removed it drops to 27mA, as soon as its plugged in jumps back up PTC Heater #1, PTC Heater #2 and 3rd seems to reset it.


Possibly the main body ECU issue that's used for transport? I did have some snow get into my in cabin filter and blower area last year from the vent/cowling (stupid Toyota design).

Going to bring to the dealer but wanted some insight from those who may have had an issue like this or just more experience than my self so i can assist the dealer in narrowing it down.

Luckily I have a AGM deep cycle battery because my 4R would be dead in a matter of days with out it. Such a bummer....


Help!
 
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Did you wait 10-15 minutes after power off for your amp draw test? Several modules take a while to power down after the ignition is turned off.

Exactly which fuse caused to amps to drop? There are several fuses for those modules. The short pin pulls power from a bunch of circuits.

Is this a new problem? Do you have a bluetooth OBD2 reader plugged in? Maybe an aftermarket alarm/tracker installed by a dealer without your knowledge? A lot of them love to do that and hack the wiring to hell.
 
So I have been having a pretty heavy Parasitic draw of about 180mA where it should only be ~50mA when the 4R is off. We pulled all aftermarket electronics and when i remove the Short pin fuse under the hood that conserves power when in transport it goes away. Think its the ECM/BCM/ECU (Not sure the terminology) when that fuse is removed it drops to 27mA, as soon as its plugged in jumps back up PTC Heater #1, PTC Heater #2 and 3rd seems to reset it.


Possibly the main body ECU issue that's used for transport? I did have some snow get into my in cabin filter and blower area last year from the vent/cowling (stupid Toyota design).

Going to bring to the dealer but wanted some insight from those who may have had an issue like this or just more experience than my self so i can assist the dealer in narrowing it down.

Luckily I have a AGM deep cycle battery because my 4R would be dead in a matter of days with out it. Such a bummer....


Help!
What year is your 4Runner? Pre TSS or after. The newer Toyota vehicles that have safety connect originally had a problem with the DCM (data communications module) always calling the safety connect phone number, thus running the battery down. For the RAV4, I know there was a T-SB on the issue to reprogram it so it didn't call so often.
 
Its a 2019.

I became aware of the parasitic draw a few months after getting my AGM battery. I had been using it for a few months with no issue but when my commute went from 1hr to 10 min I noticed the battery level dropping overnight more than what I would think. Like 12.7 to 12.3 in 15hrs. That's when I added the voltage booster to help recharge the battery when driving, plus I trickle charge once a week to maintain the batteries capacity.

I did a test when initially turning off the 4R and got ~180mA draw, let it sit for an 1/2 hour with the doors locked and it dropped to 120mA. I also brought it to my car audio place (they did my remote start with app and maestro OBD) and they tested over 5 hours after removing all the aftermarket stuff and they confirmed the 180mA draw with or without it.

Maybe I am making a mountain out of a molehill, but if i let my 4R sit for 5 days the battery would be dead. Never had that with any other car, and i have an AGM battery.
 
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Well, went to the dealer and gave them all my results and they wanted to check from scratch to be 100% sure of the draw.


Turns out no abnormal draw.......... And after everything went to sleep they measured 67mA....

I guess my AGM just has too much capacity to charge enough on my short commute (even with my voltage booster at 14.9v), and in reality the capacity isn't really that much if 60mA takes 4-5 volts over night. :noidea:
 
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If it's a push to start, I have around those same reading as well.

I have a 2016 Limited with prox key. Takes about 30 minutes to go to sleep and rest around 50 - 60ma. I also have a remote start which is about 20ma, a telematics Drone unit which is 5 - 10ma but spikes to short bursts when talking with a cell tower, and a aftermarket radio with Maestro module at around 12ma there. Dashcam also there which I havent measured but it does operate and record in an event with ignition off.

50ma should get you a week on a good, fresh battery that hasn't been drained before. Since I work from home for a while I was using a battery tender Jr with a quick disconnect cable out the front grill. I finally broke down and bought a hybrid Northstar battery from batteries+. The battery was well worth it since it's not a daily driver anymore.
 
If it's a push to start, I have around those same reading as well.

I have a 2016 Limited with prox key. Takes about 30 minutes to go to sleep and rest around 50 - 60ma. I also have a remote start which is about 20ma, a telematics Drone unit which is 5 - 10ma but spikes to short bursts when talking with a cell tower, and a aftermarket radio with Maestro module at around 12ma there. Dashcam also there which I havent measured but it does operate and record in an event with ignition off.

50ma should get you a week on a good, fresh battery that hasn't been drained before. Since I work from home for a while I was using a battery tender Jr with a quick disconnect cable out the front grill. I finally broke down and bought a hybrid Northstar battery from batteries+. The battery was well worth it since it's not a daily driver anymore.


Super helpful since i also have a similar set up remote start with drone mobil, dash cam that's off when not running as well as aftermarket radio with Maestro module. So maybe its the remote start/Alarm (Compustar) spikes to short bursts when talking with a cell tower that's doing it? I was in a place with no service.

I just went on a short camping trip and in the matter of 31 hours my Compustar remote start warned me my battery was low, actually almost dead. So I started my 4R and it just barely turned over, so i let it idol for about an hour to recharge just to be safe so I wouldn't get a warning again waking me up (I sleep in the 4R). Made it through the night and morning.

Now I am perplexed. I get this AGM battery for extra capacity and it does not make it through the night when my stock non AGM would go for days. Its not like i was running anything big or for very long. Just don't get it...... Should have been fully charged since i drove 4 hours with boost for the battery. Maybe if I don't lock the doors it doesn't go into sleep mode?
 
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I also pulled the DCM fuse which is Toyota's telematics system if you have it, and if your compustar has 2 way remotes but you use drone instead unplug the antenna. Both of those will drop the consumption some.
 
I also pulled the DCM fuse which is Toyota's telematics system if you have it, and if your compustar has 2 way remotes but you use drone instead unplug the antenna. Both of those will drop the consumption some.

Yes, 2 way and i really don't want to use the LTE drone app since I think it may be part of the issue. My old DEI/Python didn't have this issue.

thx
 
Oh, unplug the Drone module then. That's 10ma - 15ma depending on how old the module is. Pull that DCM fuse, Toyota doesn't need to keep tabs on you anyways. Note: for 2020 and newer owners, don't pull the fuse or your hands free mic stops working.
 
Figured I will update as my journey goes.

Did some amp draw testing with different doors open and letting the car sit. I can get the amp draw down to .25-.35 mA after a few minutes of sitting with the doors closed. If I open the doors it jumps pretty high to 2.0-3.0 mA+ and will lower if I turn off the interior lights. So to be expected? Should upgrade the interior lights to LED's.

I also tested the battery and did a crank test as well as a charging test which was all normal.

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So I am left with a random power consumption possibility after it sits for a while. Like the LTE of the Compustar (though when i connect with the app it doesn't draw much more) or some OBDII port Marstro connection issue that's random after it sits? Just so strange since its not showing a parasitic draw.
 
Well decided to get a new battery but they were out of Odyssey 24F so i got a Duralast Platinum AGM 24F. Figured i would see if there are any differences and take the $150 refund since it cost less and was under warranty.

Trickle charged it to be sure it was fully charged and got the same max voltage of 12.7.

Went camping with a 4hr drive, fully charged up to 12.7v and within 10 hours down to 12.3v so I had to let it run for 30min so it would last overnight. I did not lock up the car and did have all lights off but the hatch was open the entire time.

I'm lost... Clearly its charging, no major parasitic draw yet loss of .5v overnight...

Going to disconnect OBD connection for data then my LTE for my remote start and see what happens...

I may have to figure out a way to get a Tesla Powerwall to connect to my 4R. lol
 
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To add to what Jeremy556 said - there have been past threads about the Kaar alarm installed either by dealers or (as some dealers claimed) installed at the port of entry. Sold as an add on alarm the customer pays for - it's also for the vehicle to be disabled if payments are not made. Besides that, less than competent folks do the hack job installs creating future issues.

Also there is some activity that draws power after you shut your vehicle off. Not sure how long or often this happens, but the evap system pump runs occasionally to purge fuel fumes. This does make a noise, however, so if things are quiet, then it's probably not drawing current. Other than that, there shouldn't be much going on: clock, alarm system, etc.

Some of the older Toyotas had a second OBDII port under the hood. My 2000 Tundra has one. I don't think my 2013 4Runner has it - not sure of newer models. If so, there could be something plugged into it drawing power. My in the cab port on the Tundra is not powered when the key is off. I don't know about the other port - I've never used it.
 
Update!

So after many months of frustration i determined it had to be the remote start. So i called Compustar and confirmed the alarm i have with LTE pulls about 40mA, which is ridiculous. That's more than 1/2 of what the 4R should pull normally, so this makes the parasitic draw logical that i was getting and the inconsistency is due to the LTE.

So i instructed my install shop to remove the LTE and antenna. Did a long trip and no parasitic draw to the level i was getting and everything is back to normal. :rockon:
 
Update!

So after many months of frustration i determined it had to be the remote start. So i called Compustar and confirmed the alarm i have with LTE pulls about 40mA, which is ridiculous. That's more than 1/2 of what the 4R should pull normally, so this makes the parasitic draw logical that i was getting and the inconsistency is due to the LTE.

So i instructed my install shop to remove the LTE and antenna. Did a long trip and no parasitic draw to the level i was getting and everything is back to normal. :rockon:

respect for coming and concluding the thread with an update to help others
 

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