ECU-B1 fuse Parastic draw

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I’ve spent the past 3 hours trying to figure out why when I pull the ECU-B1 fuse the mA draw goes from 200mA down to 30mA. I went around each door and pulled out the connectors for the window/door locks. No change.

So frustrated, I decided to lock up my rig by pressing the FOB button. Draw went down to 30mA!

My battery dies if it sits more than two weeks without being driven. It sounds like the ECU is not going to sleep unless the rig is locked?
I guess I’ll just have to lock my rig when I park it in my garage until I figure this out.

Anyone experienced this? 1999 100 series.
 
Bump- I wonder if anyone else has this same issue but doesn’t realize it since the rig is driven daily?
 
There is a 100 series thread (or 2) on this. The consensus is that there is a small draw to handle the anit-theft stuff. I have to say, 2 weeks storage seems a little short. I think I can go 1+months w/o dead battery drain.
 
When the rig is unlocked, it sucks up 200mA of current. Arming the security system drops the current way down to the point where it will last a month or so.

I’m doing a test- parked my rig in the garage and locked it. So far it appears fine for the past couple of days. I would like to figure out why it has to be locked in order to reduce the current draw...
 
what's on that circuit? is it still the radio and dome light stuff? my year is different. Is there a deep sleep time delay on '99s?
 
so then it seems like it won't go to sleep unless you use the key fob?
 
what's on that circuit? is it still the radio and dome light stuff? my year is different. Is there a deep sleep time delay on '99s?

Not the radio. It has its own fuse. When I pull the fuse, dome lights, door locks no longer work. Anyone have info from a FSM for a 99 model year? 2003+ are different.
 
I would definitely disconnect the dome light harness and re test. You said something about door switches already but those are culprits also.
 
Here's a wiring diagram for an '04 - may be helpful to see what's on the ECM-B1 circuit even though it may be different given you have a '99?:

UZJ100 Electric Wiring Diagram (EWD) down load

Dome light is a common parasitic drain and does get shut down when you lock the vehicle. Maybe a place to start if you can't find the wiring diagram for a '99.
 
I would definitely disconnect the dome light harness and re test. You said something about door switches already but those are culprits also.
Where is this harness located?
 
ummm...... you must mean, is there an easier one than the one underneath the light cover. Of that I am unaware.
 
Well, i did find this gem of text in the FSM. This just makes it that much more difficult to track down due to the 30 minute delay. I'll have to test this out. It's almost as if I need some type of log that I can use to log the draw....

Turn Off Function
When the ignition SW turned off and there is no change in the door courtesy SW for approx. 30 minute, the DOME relay is
turned off. The DOME relay is turned on again when any of the following conditions are met.
* Ignition SW is turned from OFF position to ACC or ON position
* Change to any door courtesy SW
* Driver or front passenger door is unlocked by the key or transmitter
 
FWIW: OM states to turn light to off if parked for prolonged period of time of two or three weeks. This is because light sensor is active with lights in auto.
 
FWIW: OM states to turn light to off if parked for prolonged period of time of two or three weeks. This is because light sensor is active with lights in auto.

Lol I couldn't for the life of me figure out why my battery was getting so low just sitting and now it has been fine for a few weeks. This is the only thing I have changed. Guess I really need to read the OM lol.
 

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