2002 Battery Drain
- Thread starter shock003
- Start date
Yes, all doors closed and key in my pocket. I was thinking...maybe the DOME fuse is supposed to make a closed circuit because it goes to the clock and radio which need power to hold the memory. I have a pdf of the wiring and page 270 (for those who also have it) shows the DOME fuse going to the clock. Why the lighter works without the key is beyond me.
Good news is - I think..., when i just now tested with the multimeter on the NEG side with the damaged rear hatch wiring disconnected/unplugged, I do not see a reading - just ZERO.
So hopefully I am measuring correctly. The wires are in need of repair for sure and one completely severed (it is not the ground or the power - haven't figured out yet what it went to) So many B - Y (black - yellow stripe) wires.
I have to figure out which gauge wires I have to splice. I think most are 18 or 20 gauge, but the Blue Power one is around 12 gauge I think.
I believe it was a lucky coincidence that the DOME fuse made a test light work, but actually it is supposed to...i think.
UPDATE: With the damaged wires at the hatch totally disconnected, my cigarette lighter ONLY works with the ACC / Key turned on. As designed. So yep, the damaged wires on the hatch were indeed causing the issue! I suppose one of the wires (maybe the Black - yellow one that was totally broken) completed a circuit to the lighter. Whew. I now just need to repair the sections of wires. I may be able to go to a salvage yard for a 98 4runner to get exact wires (color/gauge) to make life a little easier and splice in good/flexible sections of the wire. Thanks for everyone's input. I got lucky because the rear hatch wiring is a common problem. So I knew where to look faster than ripping the entire car apart.
So hopefully I am measuring correctly. The wires are in need of repair for sure and one completely severed (it is not the ground or the power - haven't figured out yet what it went to) So many B - Y (black - yellow stripe) wires.
I have to figure out which gauge wires I have to splice. I think most are 18 or 20 gauge, but the Blue Power one is around 12 gauge I think.
I believe it was a lucky coincidence that the DOME fuse made a test light work, but actually it is supposed to...i think.
UPDATE: With the damaged wires at the hatch totally disconnected, my cigarette lighter ONLY works with the ACC / Key turned on. As designed. So yep, the damaged wires on the hatch were indeed causing the issue! I suppose one of the wires (maybe the Black - yellow one that was totally broken) completed a circuit to the lighter. Whew. I now just need to repair the sections of wires. I may be able to go to a salvage yard for a 98 4runner to get exact wires (color/gauge) to make life a little easier and splice in good/flexible sections of the wire. Thanks for everyone's input. I got lucky because the rear hatch wiring is a common problem. So I knew where to look faster than ripping the entire car apart.
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Well, after repairing the rear hatch wires, that was not fixing the battery drain. It did make the cigarette lighter works as designed though (only works when key ACC ON). I still can't for the life of me isolate the issue. I tried unplugging things related to the DOME fuse. As much as I can reach them anyway. I have a wiring diagram, but I do not know how to read all the junctions etc. Everything works as designed and no lights stay on. Could the door switch work fine but still be an issue? And measuring with a Digital Multi-meter isn't helping me. Not sure if I should buy a ECT 3000 to help trace the drain, but that may not help much either because the fuse is not blowing.
Surely someone out there has had a similar problem to help point to an issue. I'd hate to spend money as this is a spare vehicle with almost 300K miles and I rarely drive it, and I feel determined to trace this issue and learn the proper way. Even if I need to buy a tool like ECT3000.
Surely someone out there has had a similar problem to help point to an issue. I'd hate to spend money as this is a spare vehicle with almost 300K miles and I rarely drive it, and I feel determined to trace this issue and learn the proper way. Even if I need to buy a tool like ECT3000.
19963.4lsr5
New member
This is how I measure mine so as not to wake it up while testing by interrupting power to the pcm.
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96RedRunner
Senior Member
Your in the No two problems are the same Black Hole, vehicle specific gotta dig into it ground zero.
You got the attitude, Fluke Meter posted is Da Bomb in VOM's for mA's Instrumentation field work,
tough as nails always accurate been a favorite.
Perfect scenario problem can sit there until you work through the circuits.
Thanks for the images 19963.4lsr5. Out of ALL the you tube videos....I never saw this method for testing. I like it and may provide a better reading. My meter starts of high and then drops. Not sure what is causing that, and makes me think I am doing something wrong. Also, all the darn you tube videos neglect to show how to start tracing a drain. I would unplug items on the circuit but that doesn't help me trace the problem area. So maddening. And since my fuse is not blowing... it probably isn't a ground. I suppose I could have a relay stuck in 'open' mode. But I think the only relay on the DOME fuse is the antenna. And maybe DRL's? I disconnected the modules and no difference, but again, maybe my methods aren't the proper methods.
19963.4lsr5
New member
Let it sit for an hour and put your meter leads in amp mode and parallel the white wire.
Then remove the white wire from the post stud or bolt and see what your amp draw is and go from there.
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Then remove the white wire from the post stud or bolt and see what your amp draw is and go from there.
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Ok, I secured the door light switch and latched the door so i could lock and arm the alarm with the door open (to gain access to the fuses). I connected the DMV leads (had to clamp them) and placed them as you have with the white wire to the fuse box disconnected. and got .035-.037 reading. I then measured (with another meter) the Voltage drop across all fuses. I got Zero. hmm.
Now what made me think I had an issue on the DOME fuse was when i remove the negative cable and jump a test light between the batt. neg. post and the neg. cable = the test light lights up. if I remove the DOME fuse, it goes out.
Ok, I am measuring the battery (edit: 12.41) and see if it slowly drains, which I know it will. Any more trouble shooting ideas to proceed with? Thanks!
Now what made me think I had an issue on the DOME fuse was when i remove the negative cable and jump a test light between the batt. neg. post and the neg. cable = the test light lights up. if I remove the DOME fuse, it goes out.
Ok, I am measuring the battery (edit: 12.41) and see if it slowly drains, which I know it will. Any more trouble shooting ideas to proceed with? Thanks!
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19963.4lsr5
New member
I was always under the impression that anything less than 40ma is good.
Have you tested the amp capacity of your battery yet?
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Have you tested the amp capacity of your battery yet?
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Fuses should not have a voltage drop. If you’re trying to see how much voltage that circuit is using you will need to be part of the circuit to measure that. Remove the suspect fuse for the circuit and put a test lead at each fuse terminal.
19963.4lsr5
New member
What are your symptoms for you to look for a battery drain?
My at rest winter battery voltage is 12.3v.
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My at rest winter battery voltage is 12.3v.
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My battery is around 12.43 - I originally wrote 12.54, but I looked at what I wrote down and just measured it. My issue was a slow drain over a couple weeks and unable to start the car at all. I did have faulty wires at the hatch (3 exposed from the covering and 1 completely broke) I repaired those but still had a battery drain. But I'll see if it drops day by day like it used to.
One thing to note, I did disconnect the 4wd electrical connector from the switch to gain access to some relays behind the center console (in case I wanted to test them) otherwise everything is hooked up as normal.
Still not sure why my DOME fuse would cause a test light to light up (when I place in series with post and disconnected cable.) that tells me something is wrong. right? Meaning: if I remove the DOME fuse, the test light goes out. Maybe that is an incorrect method to test?
One thing to note, I did disconnect the 4wd electrical connector from the switch to gain access to some relays behind the center console (in case I wanted to test them) otherwise everything is hooked up as normal.
Still not sure why my DOME fuse would cause a test light to light up (when I place in series with post and disconnected cable.) that tells me something is wrong. right? Meaning: if I remove the DOME fuse, the test light goes out. Maybe that is an incorrect method to test?
19963.4lsr5
New member
Your 2002 only pulls 35ma in sleep mode. Mine pulls 26ma.
If I let my rig sit for a week this time of year it will be 12.0.
The battery can also self discharge internally depending on the batteries internal resistance as well as externally from all the grime on the battery.
You can put your meter on a battery terminal and probe around the top of the battery for places you can read voltage to the plastic.
Once a starting battery goes dead it’s never the same.
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If I let my rig sit for a week this time of year it will be 12.0.
The battery can also self discharge internally depending on the batteries internal resistance as well as externally from all the grime on the battery.
You can put your meter on a battery terminal and probe around the top of the battery for places you can read voltage to the plastic.
Once a starting battery goes dead it’s never the same.
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Ok, I am beginning to wonder if between when I had the battery go dead and now...if something got 'fixed'. I did not measure the mA in the method you sent me; so I don't have a good record of what was happening.
Over Christmas, sitting a couple weeks it went REALLY dead. I forgot to disconnect the battery. And it dropped down to 7 volts give/take. Something seriously drained it.
When I measured the volts daily (before Christmas) it would drop a little each day. So I will continue to monitor it now.
And at this point, with all the frustrations... if the battery keeps dropping like it did last fall when I noticed the problem - I am going to throw up my hands in defeat and take it to a shop.
Over Christmas, sitting a couple weeks it went REALLY dead. I forgot to disconnect the battery. And it dropped down to 7 volts give/take. Something seriously drained it.
When I measured the volts daily (before Christmas) it would drop a little each day. So I will continue to monitor it now.
And at this point, with all the frustrations... if the battery keeps dropping like it did last fall when I noticed the problem - I am going to throw up my hands in defeat and take it to a shop.
19963.4lsr5
New member
To me your battery is bad. .035 parasitic draw will not cause a couple volt drop per day.
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Well, it drops in the Tenths of a volt over day or so - and keeps dropping - is more accurate to what was happening. Not full volts. I am monitoring now to see if it is still happening. I didn't have an accurate read on the mA pull when I was experiencing major drain, so now that I do have mA, I'll see if I still have a major drain.
What troubles me (as I mentioned) is that I don't think I am supposed to be getting any test light illumination when removing the negative battery cable and placing a test light (in series) between the post and the cable. And if I remove the DOME fuse, the test light goes out. Tells me there is some sort of wiring issue. right?
What troubles me (as I mentioned) is that I don't think I am supposed to be getting any test light illumination when removing the negative battery cable and placing a test light (in series) between the post and the cable. And if I remove the DOME fuse, the test light goes out. Tells me there is some sort of wiring issue. right?
19963.4lsr5
New member
I’d have to look at your 2002 circuitry. Sometimes the dome circuit also powers aux stuff.
Is anything plugged permanently into your OBD connector?
I leave my scangauge plugged in all the time plus I have a desulfation module plugged into the battery.
I drove a little over 25 miles and parked it around 2pm and it’s already at 12.5. My dome light is LED. I don’t know if the pcm wakes up with the keyless entry or if it wakes up at key on.
Was it a bright test light or a dim test light illumination?
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Is anything plugged permanently into your OBD connector?
I leave my scangauge plugged in all the time plus I have a desulfation module plugged into the battery.
I drove a little over 25 miles and parked it around 2pm and it’s already at 12.5. My dome light is LED. I don’t know if the pcm wakes up with the keyless entry or if it wakes up at key on.
Was it a bright test light or a dim test light illumination?
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I have nothing in the OBD computer.
I did have LEDs bulbs all the way around. Nothing is lighting up (unless turned on of course).
And everything works like it is supposed to.
this is what is on the circuit:
Auto Antenna
Cigarette Lighter and Clock
Combination Meter
Garage Door Opener
Headlight (w/ Daytime Running Light)
Interior Light
Radio and Player
No idea what the combo meter is and i do not have a garage opener. (maybe those are for limited versions, i have a Sport SR5)
The test light lit pretty bright. slight less bright than compared to when i hold across the (12volt) battery posts. Can't be a horrible grounding out, otherwise the fuse would blow. I was wondering if a relay was stuck, but then logic tells me something would always operate or at least when i turn the key on.
I did have LEDs bulbs all the way around. Nothing is lighting up (unless turned on of course).
And everything works like it is supposed to.
this is what is on the circuit:
Auto Antenna
Cigarette Lighter and Clock
Combination Meter
Garage Door Opener
Headlight (w/ Daytime Running Light)
Interior Light
Radio and Player
No idea what the combo meter is and i do not have a garage opener. (maybe those are for limited versions, i have a Sport SR5)
The test light lit pretty bright. slight less bright than compared to when i hold across the (12volt) battery posts. Can't be a horrible grounding out, otherwise the fuse would blow. I was wondering if a relay was stuck, but then logic tells me something would always operate or at least when i turn the key on.
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19963.4lsr5
New member
I think the combo meter is the instrument cluster.
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