'99 LX-Dead Battery with new Battery & Alternator :( (1 Viewer)

[CanuckS100]

Hey there! I have a brand new battery and alternator, but the battery has completely drained twice.
Can anyone point me in the right direction of tracking down the gremlin or provide any options to look into?
Thanks!!

 

[YezusLX]

A starting point would be checking connections and grounding. Guess here, but if I were a betting man the ground on the alternator is not making good contact causing a drain or poor charging. If the battery light is solid (it is an alternator issue). Blinking: connection or battery. I hope this is helpful.

 

[CanuckS100]

No lights on the dash. This only happens when it sits for several days, not when I am driving it everyday.

 

[YezusLX]

Sounds like a pretty significant current draw from somewhere. Again, likely a poor connection of ground failure.

 

[medtro]

Did you have the same problem before putting in new battery and alternator? What was the reason for new battery and alternator?

 

[CanuckS100]

Did you have the same problem before putting in new battery and alternator? What was the reason for new battery and alternator?

I was solving for this issue.

 

[DrHess]

Remove the negative battery cable. Put an ammeter in series with it. What's the draw? Start removing fuses one at a time and look for when the draw stops. I have also seen alternators have bad diodes in them that will do that, even from "new" today. Easiest way to check for that is to disconnect the batter, charge it up full, hook up the battery and let it sit for hours and feel the alternator to see if it is warm. I DX'ed a MR2 that had a 2 or 3 amp drain from the alternator like that.

 

[YezusLX]

Remove the negative battery cable. Put an ammeter in series with it. What's the draw? Start removing fuses one at a time and look for when the draw stops. I have also seen alternators have bad diodes in them that will do that, even from "new" today. Easiest way to check for that is to disconnect the batter, charge it up full, hook up the battery and let it sit for hours and feel the alternator to see if it is warm. I DX'ed a MR2 that had a 2 or 3 amp drain from the alternator like that.

This ^

 

[CanuckS100]

Did that...the ECU-B circuit is the culprit!

 

[CanuckS100]

I identified the ECU-B circuit (10amp fuse) as the culprit that's draining my battery. Any suggestions on where to start tracking down the the issue within the circuit?
Where could I find a good wiring diagram?

 

[Trunk Monkey]

Combined your threads, all info in one place helps others later on.

 

[Rebus Knebus]

Where could I find a good wiring diagram?

LC100 Workshop Manual

Landcruiser 100 Series Factory Workshop Manual

lc100e.github.io

 

[medtro]

Did that...the ECU-B circuit is the culprit!

How much leak current was registered?

 

[CanuckS100]

So I just replaced the fuse and now the amps won't go back up...meaning I can't go back and get the current level. I think this could be good...odd that a fuse would solve it, but now my hi-beams automatically come and stay on when the headlights stay on. Ugh.

 

[DrHess]

My google fu said that a relay might be stuck somewhere. Given that your headlights are giving problems, I'd look at that and replace the one for high beams.

 

[CanuckS100]

My google fu said that a relay might be stuck somewhere. Given that your headlights are giving problems, I'd look at that and replace the one for high beams.

Nope, just replaced the relay and the issue remains.

 

[DrHess]

I don't see that you ever answered the question: What's the current draw?

 

[CanuckS100]

It dropped to acceptable levels after I replaced the fuse oddly enough.

 

[KliersLC]

This sounds like it could be a water intrusion issue. My Daughter's rig had some weird things going on that were "miraculously" solved by drying things out.

Any thoughts on this electrical gremlin?

Hi all! This is on my daughter's 99 with 220k. No previous electrical issues. She turned it off at work yesterday and noticed that the abs light stayed on. She didn't think much of it and went to work. 6 hours later, it was dead. After jumping and getting it home, I observed the following...

forum.ih8mud.com

 

[medtro]

It dropped to acceptable levels after I replaced the fuse oddly enough.

How did you know it was not acceptable before without knowing the number?