All,

My 2001 LS430 is showing strange electrical system behaviors. This happened this morning and all symptoms are brand new:

1) The steering wheel volume and channel select buttons do not work.
2) The steering tilt and extension do not work.
3) The radio powers off intermittantly while driving.
4) The headlights do not respond to the headlight position selection switch.
5) The wipers only turn on when in the maximum speed position.
6) The trunk and gas cap switches do not open the trunk or gas cap when pressed.
7) The gap cap opens when I shut the car off.
8) The trunk opens and closes repeately sometimes while the car is running and sometimes after I stop the car. It can go on until the battery is dead.
9) The power side window retract will retract the side windows regardless of the switch position when the car is turned off. They open sometimes when I start the car.
10) After powering off the car many of the tail lights remain illuminated. Sometimes it's all of the lights, sometimes it is just some of them. Sometimes they flicker. Sometimes the backup lights come on after shutting off the car and sometimes they come on while the car is driving.

The car is unusable in it's current state because if I leave it after driving the battery will soon be dead because of random electical components that remain on. I have to disconnect the battery in order to ensure that the car will start again.

The battery is new and not defective. The alternater is outputting 14 volts as expected. I checked all fuses and they are all ok. Does anyone have any idea what might be causing this strange behavior?

 

JUST KIDDING!! Uh, Id do a hard ECU reset and pray

 

did someone go swimming with it?

 

I left the battery off for about 45 minutes. Is that sufficient to reset the ECU or is there some other method?

 

The car was not submersed but was parked outside during a bad storm last night. Is it possible that some electrical component got wet? How should I troubleshoot this problem?

 

Sounds like you have a short somewhere. I would look and see if water possibly got in somewhere from the storm. Check your trunk and areas around the doors and firewall.

 

Modern day cars are full of capacitors that are simply "little batteries" that provide power to the many computers running a car. Some have a greater capacity than others in order to "survive" a battery disconnection.

I also drive a 7series BMW that has MANY computers. The quick n dirty reset is to unplug the battery, turn on the interior lights or leave something "on" using the cig lighter to make sure its TOTALLY drained.

leaving the battery disconnected 45mins in that car wouldnt even wipe out my radio presets


You may wannna check the drain areas in the trunk (near the Navigation or/and stereo amp) on the passenger side of the trunk. theres a panel next to the spare tire,under the carpet.

G'luck!!

 

My 2001 LS 430 just started showing similar problems:
Remote key does not work (changed the remote battery),
Only driver window can be rolled up or down but not other windows from the driver side.
All windows work, using their own key
Dome light does not come on when door opens (but works manually).
Fuel door and Trunk opener do not work (I pushed and released the security bottom).
headlights would remain on (on auto) after car is turned off.
Front doors will not shut by themselves (soft touch) but rear doors work fine.
Seat belt height adjuster does not work
Seat memory does not work
Power door locks don't work.
Head light washers do not work but seat heaters and other keys on the dash do work.

Any help appreciated!

 

There must be an unusual load. In order to find out what it is, check the currents of fuses. There are many and you might think it's not easy but to do this, you don't need to remove fuses. All you need is a digital volt meter or a multimeter which can measure down to 1mV or less and your some efforts. Every fuse has some small resistance and this causes a small voltage drop.

All you do first is just to measure the dropping voltage at each fuse applying two voltmeter's leads to the holes located at top of the fuse. You can see the small metal piece under the hole. Those metals are connected to both sides of the fuse element and you can check the voltage between them. Most of them shows just 0 or a few mV but certain line(s) must be much bigger than that.

Inform me which line(s) is(are) so.

Incidentally, I came over here requested by one of the moderators. I am not quite familiar to LS430 but I own a JDM Celsior UCF21 and I know some about electrical area of LS series.

 

Thank you Yamae;
I did pull out and checked most of the fueses (and there is a lot of them!). I will check again, reading the voltage / resistance using your suggestion.
Given that so many devices are not working, and I dont see the connection between them, I feel there must be an issue with one of the logic driver boards or one of the computers. headlights dont go off after a minute as they should when set on auto which means what controls the timing of the lights is noty working. Dome light does not come on when opening the door but it does come on when I turn off the car and remove the key!
Do you think diconnecting battery may help to reset everything back to factory setting or will it cause more problems?
Thanks for jumping in to help.

Hamid

 

Wow, what a crazy set of problems. As mentioned, it sounds like a major short somewhere and its affecting the various ECU's throughout the car. Any indication of water getting inside the car?

 

LS430 readers should know that Yamae-san is being very modest when he says he knows some about electrical area.

 

I figured out my issue. I had water coming in from the driver side tail light lens, it was missing the rubber seal. Water had rose to the level under the trunk floor driver side channel so that it flooded the ECU back there. Replacing the board in the ECU did the trick.

 

Great to hear you figured it out.

 

There must be some unusual current supply caused by unwanted power distribution. Sounds like a totally different issue from the thread. All you need first is to find out the line which doesn't supply the DC12V.