Tracking Down Battery Drain (2 Viewers)

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Nov 15, 2019
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Arlington, TX
Been working on my son's FJ40 and think that there is something draining the battery.

Many times if the 40 has been sitting overnight, when he tries to start it, the starter will just "Click". it was doing that this morning and I threw some jumper cables on it and it fired right up.

Thus far, I have removed the negative battery cable and attached a trouble light to it. When I touch the testing light to the negative terminal, it glows.
  • I have pulled the fuses one by one and tested the negative terminal with the light and it still glows.
  • I have pulled the plug and cable off of the alternator and it still glows.
  • I have pulled the plug on the voltage regulator and it still glows.
  • I have removed every stereo amp wire off of the terminals and all other non-necessary wires off of the battery terminals and it still glows.
  • Unplugged the 3 ignition switches coming out of the steering column -
  • I hooked up a voltameter with the black going to the negative wire and the red going to the terminal and it is at 12.9V
Either my idea of trying to narrow this down with a testing light is barking up the wrong tree or I am missing something.... any ideas!
 
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Disconnect the ammeter, and about all you're left with is the starter motor
 
Disconnect the ammeter, and about all you're left with is the starter motor
Welllll, In another post yesterday, I was asking questions about a starter solenoid that we had stick open. The bad starter is from Oreilly's - roughly 1 month old. We took it back to O'reilly's and got a replacement starter - we installed it and every once in a while, we would see a spark jump from the starter to the block. Any thoughts?

Looking to buy an GR starter for an FJ60
 
Where does the spark jump exactly?
Sounds like it needs a good clean out, and maybe a rebuild
 
Where does the spark jump exactly?
Sounds like it needs a good clean out, and maybe a rebuild
The starter unfortunately is a remanufactured starter from Oreilly's. It is brand new. After we installed it last night, we saw the spark and called Oreilly's and said that we needed another one. I don't know if the starter is the culprit of the spark or if there is something else going on. The new replacement starter should be in tonight, but I won't be able to get it installed until tomorrow.
 
I am soooo tempted to pull all of my hair out.

In the process of trying to see what may be the possible drain. I have disconnected and reconnected everything that I think it could be. Key word... reconnected.

Now, after reconnecting everything. I am trying to start the 40 and it will crank, but immediately dies.

I AM SO FRUSTRATED!!! Any ideas?

I have made sure that the coil wire has been reconnnected.
 
I am soooo tempted to pull all of my hair out.

In the process of trying to see what may be the possible drain. I have disconnected and reconnected everything that I think it could be. Key word... reconnected.

Now, after reconnecting everything. I am trying to start the 40 and it will crank, but immediately dies.

I AM SO FRUSTRATED!!! Any ideas?

I have made sure that the coil wire has been reconnnected.
This is caused by the key switch connection from the Run position feeding the coil - could be just that the key switch connector needs re-seating.
The crank position uses a separate feed to the coil - that's why it starts but won't run
 
Wouldnt disconnecting the wire from the back of the alternator do the same thing, or does the wire on the back of the alternator go to the voltage regulator
No. The ammeter feeds almost everything on the truck, so if you remove one lead from it, then you have almost nothing connected to the battery.
 
The starter unfortunately is a remanufactured starter from Oreilly's. It is brand new. After we installed it last night, we saw the spark and called Oreilly's and said that we needed another one. I don't know if the starter is the culprit of the spark or if there is something else going on. The new replacement starter should be in tonight, but I won't be able to get it installed until tomorrow.
If you're seeing a spark while cranking, then might be just a sign of a bad connection - maybe take a photo and point to where the spark was?
Disconnect the starter motor and solenoid and see if you lose your drain
 
I recommend disconnecting the battery from the car. Charge the battery. Check the voltage. Let it sit overnight and test the battery in the morning. Doing this to determine if the battery has low internal resistance ( ie a bad battery).

Or - take the battery into O’Rielly and have them test the battery.

With the car in the off setting on the steering wheel - there should only be a couple of circuit that have power. ( lights, Brakes, horn, cigarette lighter). I would use a multimeter on those fuse terminals to see if you have any current.
 
This is caused by the key switch connection from the Run position feeding the coil - could be just that the key switch connector needs re-seating.
The crank position uses a separate feed to the coil - that's why it starts but won't run
It looks like the reason that the 40 would crank was due to a fuse issue. While trying to track down the possible causes for the battery drain. I pulled each fuse individually to see if there was a continued drain. after checking I would replace the fuse. It appears that there was som corrosion on the fuse block. I had 12 volts on one side of the block but not on the other due to the corrosion. Talk about a headache. I spent 6 or so hours chasing my tail only to find out it was corrosion causing the issue.
 
It looks like the reason that the 40 would crank was due to a fuse issue. While trying to track down the possible causes for the battery drain. I pulled each fuse individually to see if there was a continued drain. after checking I would replace the fuse. It appears that there was som corrosion on the fuse block. I had 12 volts on one side of the block but not on the other due to the corrosion. Talk about a headache. I spent 6 or so hours chasing my tail only to find out it was corrosion causing the issue.
I am still trying to figure out what the potential battery drain could be.
 

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