Looks like ToyoDIY doesn't have wiring diagrams anymore, or I'm just not finding them. Do you have a source for electrical diagrams for your car?
Parasitic drain - 2015 Toyota 4Runner
- Thread starter RichardZ
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I'll try disconnecting the alternator tonight.
Since when I close the doors the dome lights go out, I was assuming that the door switches are good. Would this be correct? Thanks..
In theory yes, light will go out. Lack of a wiring diagram, and experience with stupid designs and electrical wizardry, it's possible that there can be two circuits for those latches. One to turn off light and one to send signal to ECU for safety reasons. (some hood latches won't let car start, and also not connected to a light)
Start with the alternator. I would disconnect both the B+ terminal and control connector. Do them one at a time see which makes a difference. You can isolate the alternator or control circuit doing it that way, and insure you dont waste money on an Alternator when there can be a short or component failure upstream of connector.
I’m having no luck finding a wiring diagram.
Pay the $20 and get 2 days on TIS.
https://techinfo.toyota.com/techInf...nfpb=true&_pageLabel=ti_home_search_docs_page
What does the security system look like on that thing. Does it show its active in the dash when locked (my nissans show a key, and I think our Rav has a flashing light. A bad door switch possibly is not allowing the security system to enable or something.
100mA would be about right.
Will be surprised if its your alternator - 100mA sounds like too little. Easy to isolate however.
Door lock mechanisms have been the culprit for me on this problem many times. If you have a bad latch its constantly checking to see if its closed. Usually find someone has shut off the dome light to remedy the draw but it only fixes part of it.
Here are some diagrams, I highlighted the relevant circuits, it appears there is a large junction block behind the gauge cluster that may help in halving the circuit for testing.
Put a charger / tender on the battery and then in the morning, when it's cool, scan the wiring / ECMs / relays with a thermal camera. 500mA @ 12VDC is about 6 Watts of heat going somewhere.
That's a really sharp idea!
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I cannot recommend enough the Amp Hound. Super simple and less than 30 minutes to track down even the most difficult to find parasitic drain. Every good mechanic has one in their tool kit.
From bad to worse:
1. I went to start the car today and had a no start condition. Nothing. Battery voltage good. Lots of lights on the dash. I did a scan and got 14 communication errors. Sample screenshot >
1. I went to start the car today and had a no start condition. Nothing. Battery voltage good. Lots of lights on the dash. I did a scan and got 14 communication errors. Sample screenshot >
2. Then when trying to start the car one of the rear brake lines decided to brake open a start spilling brake fluid.
Sucks..
Sucks..
Thanks for taking the time to do this.!
The no start condition was a blown AM1 fuse. Back to square one + a brake line repair.
Aftermarket alarm/tracker/remote start? Even if not activated many dealers install this trash.
Beyond that, do you use the toyota app telematics feature? Does it even have one? I know some people had issues with pre-4G (circa 2015 or older) GM vehicles where the telematics (OnStar) module was always searching for signal even though the towers it used were no longer active, draining the battery.
Beyond that, do you use the toyota app telematics feature? Does it even have one? I know some people had issues with pre-4G (circa 2015 or older) GM vehicles where the telematics (OnStar) module was always searching for signal even though the towers it used were no longer active, draining the battery.
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Never had alarm or tracker on any of my new vehicles. I don't pay for those options. Remote start is included.
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Parasitic draws can be a pain in the butt to find sometimes.
Those codes could be because of loss or low voltage. They could have been impending after you replaced the battery.
Again, what's causing the no start condition? I know that's the obvious question, but like I said, hood latch May do that.
One thing I forgot to mention, check for signs of obvious corrosion. Areas of previous water leaks, fuse box, battery cables. A circuit can be closed because of corrosion. I know you pulled all fuses and that should have isolated things for you, but corrosion can do funny things.
Again, what's causing the no start condition? I know that's the obvious question, but like I said, hood latch May do that.
One thing I forgot to mention, check for signs of obvious corrosion. Areas of previous water leaks, fuse box, battery cables. A circuit can be closed because of corrosion. I know you pulled all fuses and that should have isolated things for you, but corrosion can do funny things.