Fuse block corrosion causing parasitic battery drain. 99 LC (3 Viewers)
- Thread starter MNXJ1996
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- Thread starter
- #22
OK, I have some more time to work this out. I talked to the actual tech that was doing the work at the Toyota dealer. He told me that he traced the draw the fuse box under the kick panel due to corrosion. He said that when the vehicle was shut off and locked that the computer was not being told it was off was not going to "Sleep". He said this was causing the battery drain. He said he played around with the connectors and got some corrosion removed and the vehicle started behaving normal. He recommended that the owner replace the corroded junction box to prevent it from happening again. Apparently the previous owner decided they had enough and traded the car at another dealer.
Is it necessary to replace the entire box? It's likely one terminal causing your issues which might be cleanable/repairable. It's a tight akward area to work in but might be worth a try to remove & inspect the fuse panel clean the contacts and re install.
The junction block is pretty simple to remove. A buddy of mine had mine out in about 10 minutes, but of course he does auto body repair work for a living. I believe he said there were 4 wiring connectors. (You can search "fog lights not working" for more information on this block) I would try to take it out and try to clean it up and spray some contact cleaner on it before you spend a lot of money replacing it.
- Thread starter
- #25
Yes, it looks relatively simple to remove, I will try that first. I will pick up some contact cleaner and give it a try. Toyota tech also recommended checking the passenger side junction block to be sure also.
I do appreciate the help here!
I do appreciate the help here!
- Thread starter
- #26
I ended up buying the LC. Dealer took 4k off the price and after cleaning the connectors with contact cleaner I havent had a problem. If it comes back I will replace the junction block.
I have tried everything to replicate a water leak. It rained here quite a bit last week, garden hose, high pressure car wash. So far I cant find a trace of water inside or anywhere under the dash.
Again thanks for the help!
I have tried everything to replicate a water leak. It rained here quite a bit last week, garden hose, high pressure car wash. So far I cant find a trace of water inside or anywhere under the dash.
Again thanks for the help!
I’m glad to see this in writing somewhere. If my 100 sits for more than a couple of days, I can pretty much expect it to struggle to start. I just got back from vacation, and it was super dead. As I’ve been messing with it today, I noticed the headlights were in “auto”, which I’ve been more mindful of not doing, but I must have had a brain fart before I left town. I’ll try to be more careful with it.
I never accidentally left my lights on when I drove a 3rd Gen Prelude in the 90s! That was one good thing about pop up headlights, they were physically visible from the driver’s seat.
2 or 3 days with light switch in auto, will not drain a good fully charged battery. Even a week shouldn't cause a struggle to start. Two to three weeks, may drain to point, weak no start. Make sure you've a good battery, post & clamp clean and greased with white lithium.
Note: Keep in mind. a battery not kept full charged, will sulfate. Then it will not accept a full charge.
Note: Drop down with DVD player in cargo area on right side. They a notorious parasitic draws on battery. They will weaken a battery fast in 2 or 3 days. Some headrest DVD players will also.
In my master thread in Snowy's (06LC) thread. I show a fuse that's under the glove box. Pulling it out, will stop the parasitic draw for cargo DVD.
Thanks for the ideas. I do think I’ve got something else going on besides the auto lights (when I forget to turn them off).
No DVD in my 2000 LX470. Any other ideas of what to check next? Got 280k miles, could be anything. I noticed a comment above about fog lights…. Mine don’t work either. Related possibly?
I had no trouble with the battery for the 1.5 years or so that I have owned it. The problem started up about 6 months ago. I try to at least drive it around the block every day to keep it charged up. It’s actually my 3rd option, so it is really easy to let it sit for a week here and there. Honestly I wouldn’t even know it had an issue if I didn’t have the occasional week that it would sit.
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Very often, a battery only about 1 yrs old, that then starts giving problems. Is due to charge being inhibited.
How about, you post a picture of your battery?
Any aftermarket item wired in, is always my first suspect, after battery, cables and alternator.
Battery post:
As stated above, battery post need to be keep clean. Toyota does not recommend greasing post and clamps. But I always do, after I clean them. I've used white lithium grease on cleaned post & clamps, since I was a teenager. Why, well my GTO battery keep getting too weak to crank engine. I'd scrape the post until the gray removed and nice shinny silver again, with my pocket knife. It would then start. Somewhere along the way, someone told me to add the while lithium which will aid in prevent oxidation (the gray). I did, and never again had starting/cranking issues from a good battery related issue.
Note: IIRC 00LX OM calls for group 24F battery. I use as does most Toyota & Lexus Dealerships in this region, group 27F.
Battery Cables.:
Looking at batteries and cables I so often find post & clamps covered in a white build up of dry acid. I've found it so bad in some, it has gotten deep into wire block hanging off battery positive post. This is from neglecting to clean acid battery on regular basis with baking soda & water mixture. Baking soda neutralize acid. Which we must do as we wash the acid off. Or we'll damage any metal part the acid washes onto. It also neutralizes acid at ends cables.
Over time our cables do get oxidation in the sheathing. If you look at the ground wire coming of battery attached to fender. You'll likely see some blue. The blue is oxidation, that if seen at ends. You can bet is going in under sheathing.
Oxidation increase resistance:
When battery post, clamps or wiring builds up oxidation. Resistance goes up. This inhibits current flow to battery, motor and all electrical components. Just like using a drill or vacuum cleaner, etc., on a long to small/undersized gauge extension cord. You can actual feel the excessive resistance, in the from of heat coming off the extension core. This resistance reduces current flow (AMP) to motors. Which burns up motors. It also reduces AMP to battery. Battery will then not get a full charge, and be damaged (sulfate).
Some do what's called the Big 3. Replacing battery and alternator cable with new and often heavier gauge cables. Search mud and google it. But in most cases ours cables are good enough if not neglected.
Alternator:
Once we've battery and cables in proper working order, we need to test alternator. Many you tube videos on this. Or just drive to a NAPA (most any parts store) and they test for you.
Parasitic drain or draw:
Now that we've battery and charging in proper working order. We can move (if needed) to checking for parasitic drain on battery. Here again just google it, and you'll find many helpful videos on how to.
They can come from fuse box. But not common (in this region), if battery maintained properly IMHO.
They can be as simple as glove box light not going out.
If a door switch not function properly, this can also be the issue. But you should see dash warning light indicated a door open.
Pictures of Neglected battery damages clamps and cables:
During and after neutralizing with baking soda.
This negative cable still showing blue (acid) when water & baking soda added repeatedly 20 times over 2 days.
Battery (dry) acid deep into wire block
How about, you post a picture of your battery?
Any aftermarket item wired in, is always my first suspect, after battery, cables and alternator.
Battery post:
As stated above, battery post need to be keep clean. Toyota does not recommend greasing post and clamps. But I always do, after I clean them. I've used white lithium grease on cleaned post & clamps, since I was a teenager. Why, well my GTO battery keep getting too weak to crank engine. I'd scrape the post until the gray removed and nice shinny silver again, with my pocket knife. It would then start. Somewhere along the way, someone told me to add the while lithium which will aid in prevent oxidation (the gray). I did, and never again had starting/cranking issues from a good battery related issue.
Note: IIRC 00LX OM calls for group 24F battery. I use as does most Toyota & Lexus Dealerships in this region, group 27F.
Battery Cables.:
Looking at batteries and cables I so often find post & clamps covered in a white build up of dry acid. I've found it so bad in some, it has gotten deep into wire block hanging off battery positive post. This is from neglecting to clean acid battery on regular basis with baking soda & water mixture. Baking soda neutralize acid. Which we must do as we wash the acid off. Or we'll damage any metal part the acid washes onto. It also neutralizes acid at ends cables.
Over time our cables do get oxidation in the sheathing. If you look at the ground wire coming of battery attached to fender. You'll likely see some blue. The blue is oxidation, that if seen at ends. You can bet is going in under sheathing.
Oxidation increase resistance:
When battery post, clamps or wiring builds up oxidation. Resistance goes up. This inhibits current flow to battery, motor and all electrical components. Just like using a drill or vacuum cleaner, etc., on a long to small/undersized gauge extension cord. You can actual feel the excessive resistance, in the from of heat coming off the extension core. This resistance reduces current flow (AMP) to motors. Which burns up motors. It also reduces AMP to battery. Battery will then not get a full charge, and be damaged (sulfate).
Some do what's called the Big 3. Replacing battery and alternator cable with new and often heavier gauge cables. Search mud and google it. But in most cases ours cables are good enough if not neglected.
Alternator:
Once we've battery and cables in proper working order, we need to test alternator. Many you tube videos on this. Or just drive to a NAPA (most any parts store) and they test for you.
Parasitic drain or draw:
Now that we've battery and charging in proper working order. We can move (if needed) to checking for parasitic drain on battery. Here again just google it, and you'll find many helpful videos on how to.
They can come from fuse box. But not common (in this region), if battery maintained properly IMHO.
They can be as simple as glove box light not going out.
If a door switch not function properly, this can also be the issue. But you should see dash warning light indicated a door open.
Pictures of Neglected battery damages clamps and cables:
During and after neutralizing with baking soda.
This negative cable still showing blue (acid) when water & baking soda added repeatedly 20 times over 2 days.
Battery (dry) acid deep into wire block
