LS - 3rd Gen (2001-2006) Discussion topics related to the flagship Lexus LS430

2004 Water Leak - various electrical issues

Old 11-30-14, 02:03 PM
  #1  
kermitxc
Rookie
Thread Starter
 
kermitxc's Avatar
 
Join Date: Dec 2013
Location: Texas
Posts: 63
Received 10 Likes on 5 Posts
Default 2004 Water Leak - various electrical issues

this has happened twice already in the last 7k miles (2nd owner, purchased 3 months ago with 83k miles)

first time after a big pour down driving on 60mph on the highway, yesterday after car wash. Here are the identical symptoms:

- only driver window will roll down with engine running
- ignition on ACC all windows roll down fine
- mirrors don't fold down, adjust or automatically tilt in reverse
- first time the open door sensor was misreporting

everything else seems to be working fine, AC works, engine/shifting seems fine. Problem fixes itself after few hours (dries out I assume)

anybody know what is going on?
Old 11-30-14, 05:22 PM
  #2  
reozone
Driver School Candidate
 
reozone's Avatar
 
Join Date: Nov 2013
Location: Ohio
Posts: 23
Likes: 0
Received 6 Likes on 5 Posts
Default

You might try looking at the computer located in the driver's side footwell (I believe its behind the emergency brake pedal). Anyway, this has several connectors going into it around the sides, and you might have corrosion issues starting with some of those connectors. Our 2001 LS430 started doing all sorts of strange stuff a few years ago and it was always worse when it had rained or was very humid. Somehow, water was getting down inside the car and dripping on the computer. Over time, this resulted in some corrosion and eventually caused intermittent connections to develop. I was able to fix the problem by disconnecting the computer, carefully soaking just the connector ends in an undiluted vinegar solution for several hours which dissolved the corrosion (greenish looking stuff mostly), then cleaning with distilled water and drying with a blow dryer. I did the same thing with the connectors on the harness side, which was a bit more difficult since I was unable to remove the harness. Everything got coated with dielectric grease, reassembled, and for safe measure, the top covered with plastic film. I haven't had a problem since. As far as where the water was coming in from, my best guess was something to do with the sunroof. There are drain holes on each side that go down the frame next to the windshield. You might look for some cracks or rust in that area. There may also be a leak around the windshield itself. Have you had yours replaced recently? I did a little repair/waterproofing in that area and haven't noticed any water or wet spots in the driver's footwell since. Maybe I got lucky. Hope this helps.
Old 12-01-14, 12:55 PM
  #3  
kermitxc
Rookie
Thread Starter
 
kermitxc's Avatar
 
Join Date: Dec 2013
Location: Texas
Posts: 63
Received 10 Likes on 5 Posts
Default

that's very helpful - thanks. Is it easy to get to the computer?
Old 12-01-14, 03:18 PM
  #4  
reozone
Driver School Candidate
 
reozone's Avatar
 
Join Date: Nov 2013
Location: Ohio
Posts: 23
Likes: 0
Received 6 Likes on 5 Posts
Default

I'd say it was medium difficult. The carpet had to be peeled back (which was wet by the way), the P-brake ***'y moved out of the way, and then I believe the computer was accessible. I'm a bit foggy on details since it was about 4-5 years ago. If you are mechanically inclined, I would say go for it, but don't start during the week unless you don't need to drive the car. Also, If you don't see any signs of corrosion or moisture, this may not be your culprit and the problem would lie elsewhere where something similar is happening.
Old 12-01-14, 03:52 PM
  #5  
Tom57
Pole Position
 
Tom57's Avatar
 
Join Date: Mar 2008
Location: Illinois
Posts: 2,146
Received 67 Likes on 63 Posts
Default

Originally Posted by kermitxc
that's very helpful - thanks. Is it easy to get to the computer?
Just to be clear, it's the junction / fuse block ECU located on the driver's side foot well. These are generally available from auto recyclers for less than $200. These do go bad on high mileage northern climate LS's. Suggest that you check the owner's manual to learn what accessories that fuse box controls. In addition to fuses, there are electrical relays as part of this J/B.

Last edited by Tom57; 12-01-14 at 03:56 PM.
Old 07-16-22, 08:45 AM
  #6  
TonyCee
5th Gear
 
TonyCee's Avatar
 
Join Date: Jul 2022
Location: Virginia
Posts: 5
Received 1 Like on 1 Post
Default Water leak

Originally Posted by reozone
You might try looking at the computer located in the driver's side footwell (I believe its behind the emergency brake pedal). Anyway, this has several connectors going into it around the sides, and you might have corrosion issues starting with some of those connectors. Our 2001 LS430 started doing all sorts of strange stuff a few years ago and it was always worse when it had rained or was very humid. Somehow, water was getting down inside the car and dripping on the computer. Over time, this resulted in some corrosion and eventually caused intermittent connections to develop. I was able to fix the problem by disconnecting the computer, carefully soaking just the connector ends in an undiluted vinegar solution for several hours which dissolved the corrosion (greenish looking stuff mostly), then cleaning with distilled water and drying with a blow dryer. I did the same thing with the connectors on the harness side, which was a bit more difficult since I was unable to remove the harness. Everything got coated with dielectric grease, reassembled, and for safe measure, the top covered with plastic film. I haven't had a problem since. As far as where the water was coming in from, my best guess was something to do with the sunroof. There are drain holes on each side that go down the frame next to the windshield. You might look for some cracks or rust in that area. There may also be a leak around the windshield itself. Have you had yours replaced recently? I did a little repair/waterproofing in that area and haven't noticed any water or wet spots in the driver's footwell since. Maybe I got lucky. Hope this helps.
Sounds like you have a leak at your drivers side moonroof drain, which allows water to leak on your fuse box (by your left foot). This is where my problem was discovered, Tony.
Old 07-16-22, 10:06 AM
  #7  
VolumeToo
Pit Crew
 
VolumeToo's Avatar
 
Join Date: Apr 2017
Location: Essex, UK
Posts: 213
Received 22 Likes on 19 Posts
Default

I happened to stumble on a video where an engineer was tracing the exact same fault - only the drivers window working. It turned out to be the overhead panel with the dome light / moonroof controls. Maybe if you pop that out and disconnect it from the BEAN bus, everything else will start working.

Last edited by VolumeToo; 07-24-22 at 07:21 AM.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
TerrySaur
RC - 1st Gen (2015-present)
19
02-14-22 03:51 PM
winter4w
LS - 1st and 2nd Gen (1990-2000)
15
05-14-18 06:33 PM
cbgdjg
SC430 - 2nd Gen (2001-2010)
1
07-26-16 09:21 AM
Toyoboy
GS - 2nd Gen (1998-2005)
2
08-31-12 08:47 PM


Thread Tools
Search this Thread
Quick Reply: 2004 Water Leak - various electrical issues



All times are GMT -7. The time now is 07:21 AM.