Battery Drain 1993 80 Series Land Cruiser (1 Viewer)

[Quicksand80]

Hey all, I am seeking advice on identifying the cause of an electrical draw on the battery in my 1993 80 series LC.

Here is what I've done so far:

• I bought a new AGM battery from Costco
  • The previous battery was ~7 yo
• I cleaned up all of the engine ground wires and other ground wires I could find
• Installed a new started (reman)
  • I tested the old one before I replaced it and the test showed it was still "operational"
  • I cleaned up the leads before connecting
• Checked all fuses and replaced two
• Repaired some wiring from the PO near the oil pressure sender unit

Some additional information about the rig:

• No remote start, alarm system, aftermarket lights, or aftermarket stereo.
• I've looked at as much of the wiring harness as I could access. The only thing I've seen that was out of place was some weird incision from the previous owner near the oil pressure send unit (passenger side).
• I replaced the alternator two years ago with a new 80 amp unit from rockauto
  
  .

Sadly, none of these things have alleviated the issue. While wrapping things up and attempting to hook up the new battery, the starter started making noise (spinning) and then letting some smoke out. This happened twice, and I have not attempted to hook up the battery again.

I feel like I am running out of ideas on how to fix this issue. I plan on testing the relays tomorrow, but I would also appreciate any tips and leads on things I should look at or try.

TIA!

 

[greentruck]

Sounds like a starter circuit issue somehow. Any issues with the ignition switch that you've noticed? This is a known failure point in this circuit, but maybe one you've not looked into yet?

 

[jonheld]

While wrapping things up and attempting to hook up the new battery, the starter started making noise (spinning) and then letting some smoke out. This happened twice, and I have not attempted to hook up the battery again.

Starter solenoid plunger and contacts welded together.
These trucks will spit out aftermarket starters and alternators. Denso is the OEM for Toyota for both.

 

[TheBussman]

unplug the starter trigger (small ) wire and reconnect the battery, see if it still happens. if so jonheld is right. and he is defiantly right about using quality parts. sounds like you may have another issue on top of that if you've been chasing this for more then 2 years (sounds like from your post)

 

[LandLocked93]

Hey all, I am seeking advice on identifying the cause of an electrical draw on the battery in my 1993 80 series LC.

Here is what I've done so far:

• I bought a new AGM battery from Costco
  • The previous battery was ~7 yo
• I cleaned up all of the engine ground wires and other ground wires I could find
• Installed a new started (reman)
  • I tested the old one before I replaced it and the test showed it was still "operational"
  • I cleaned up the leads before connecting
• Checked all fuses and replaced two
• Repaired some wiring from the PO near the oil pressure sender unit

Some additional information about the rig:

• No remote start, alarm system, aftermarket lights, or aftermarket stereo.
• I've looked at as much of the wiring harness as I could access. The only thing I've seen that was out of place was some weird incision from the previous owner near the oil pressure send unit (passenger side).
• I replaced the alternator two years ago with a new 80 amp unit from rockauto
  
  .

Sadly, none of these things have alleviated the issue. While wrapping things up and attempting to hook up the new battery, the starter started making noise (spinning) and then letting some smoke out. This happened twice, and I have not attempted to hook up the battery again.

I feel like I am running out of ideas on how to fix this issue. I plan on testing the relays tomorrow, but I would also appreciate any tips and leads on things I should look at or try.

TIA!

Did this draw start suddenly or you just happened to notice one day?

Put a voltmeter across the batt terminals (measuring current) with truck off/key out. Given that you explained there are no devices acting parasitic (constant power consumers), does the voltmeter show more than 250mA? If so, how much over 250mA?

An alternate approach would be to attempt to isolate the circuit causing the draw.
You can start by pulling one fuse at a time, one after another. Watch the voltmeter for a drop in the draw current between each fuse pull.
Or you can pull all the fuses to start, then replace each one at a time, measuring the current increase between each replacement.
Naturally, a noticeable change in current flow with a pull/replacement of a single fuse narrows down the circuit you should focus on. ( If that current draw is outside native specs for that circuit)
If current draw does not change with all fuses removed, then suggest focusing on ground connections. But it sounds like you've done much of that already.

Let us know what you find.