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Discussion Starter · #1 ·
Hey guys, I've had this car in my shop for a week now and I've been tinkering with it a little bit here and there, trying not to spend too much time on it because the owner isn`t planning on paying an exorbitant amount for me to find the issue, but I'm stuck Here's the details

It's a 2006, 2.3L. It is drawing 120ish mA while sitting. Enough to kill the battery in a couple days. Acceptable current draw should be 50ish according to my experience. I've narrowed it down to the door trigger circuit. I've attached the schematic. My ammeter is hooked up in series in place of the 40A BTN fuse

Here is the weird part, read carefully: The drain goes away when I open all the doors. I have the interior lights all off (except for the ignition light, door open light, and dim blue dash courtesy lights which come on when the driver`s door is opened, I have also accounted for these lamps being on in my calculation).

For example: 120mA draw with all doors closed, I open one door, now its 110, open another door, now its 90, open the 4th door and it goes down to 70mA...which I can get down to just above 50 if I disable the warning and courtesy lights

Logically, the circuit should draw more amperage when I open doors...especially the drivers door. According to the schematic, the bcm is seeing ground through the door triggers, when the door is opened it opens the circuit and cuts that ground off. I`m kinda stumped on what else to try. Any bright ideas from the community
 

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Fellow tech here. Since the wiring diagram shows each door ajar switch as having its own input into the BCM, I would see if you can access a live data PID that indicates what doors are open. If you can, see if it's working correctly. Another thing to do would be to unplug the BCM and make sure that none of the wires for the door switches are shorted to voltage or ground.
 

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Discussion Starter · #3 ·
Fellow tech here. Since the wiring diagram shows each door ajar switch as having its own input into the BCM, I would see if you can access a live data PID that indicates what doors are open. If you can, see if it's working correctly. Another thing to do would be to unplug the BCM and make sure that none of the wires for the door switches are shorted to voltage or ground.
Thanks. I don't think my scan tool will give me that data but all the doors individually activate the light on the dash. I'll test those inputs at the bcm tomorrow
 

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JMO that a 10-20mA draw per 'event' doesn't seem high enough to be anything purely electrical, and must be an electronic/computer draw instead. For instance, if the microprocessor has become defective and is staying active by repeatedly running some code related to each door being closed, that would explain why the draw drops each time a door is opened. Just speculation of course about the specifics, and it could be many other scenarios as well.

Perhaps you can rig up your meter in series with the microprocessor power pin/wire (one of the 2 coming off the fuse on the left side of the wiring diagram) instead of the fuse, in order to see if that's where all of the extra draw is coming from?
 

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the battery needs to be slowly recharged...
taking the battery cable off with the engine running is so 1960.. do that with new cars and you can blow the alternator diodes . you can also blow up other computer modules..
When did any of us mention charging a battery or unhooking the battery while the car is running?
 
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