Okay, turn them off manually...try that.

 

The switch is on your lower drivers side dash. This will require you to use the key to unlock the doors.. I know this along with the headlights shut off manually helped me...

btw...not sure if the auto wheel thing helped but i shut it off anyway when the vehicle sits for more than 3 days...

 

are you still able to arm the car?

 

REALLY!!!!!??????? Damn!!! I sooo gotta start turning off the light switch now!!!!


Thanks OLT!

 

Of course, you just have to hit the power door lock button by your window controls on your way out, or exit the car, close the door and turn the key to lock it. This switch only disables the remote keyless entry function, it doesnt disable the entire security system. If you are unsure, try flipping the switch to off, then get out of the car, lock the doors with your windows rolled down, close the door, unlock the door by sticking your hand inside and turning the lock, then open the door, and the alarm WILL go off.

 

There must be some other issue here...I don't think your problem is the result of either the remote lock switch or the auto steering switch or even the headlight switch.

The drain from the receiver for the remote lock is negligible and nowhere near enough to drain a healthy battery in three days. As for the auto steering switch, the steering wheel isn't even activated until the key is placed into the ignition (for my 90 LS, anyway), so I doubt that this is drawing juice when the car is parked and off. Finally, the headlight wiring is designed so that if the headlights are in the 'on' position and the the car doors are opened after the ignition is off, the circuit is opened and the lights shut off. Once this is the case, there is no more draw from the battery.

There must be something else at work here that is draining your battery. Is one of your courtesy lights left on by mistake? Do you have aftermarket radio or lighting that might be improperly wired? Have you had any work done that required electrical re-wiring?

Is your battery in good health? After frequent repeated full discharges, car batteries are weakened...perhaps this is exacerbating your situation because your battery is not holding a charge as well anymore. Is your charging system in good working order? If the voltage being put out by the alternator is out of spec--high or low--this will also have an adverse affect on the battery.

Electrical issues are notoriously time-consuming to diagnose and require a significant degree of knowledge...but I am surprised that Lexus gave up on it.

For what it's worth, I've left my car parked for a little over a month and it started right up when called upon, without having to disable any of the switches above or disconnect the battery...but if any of those tips help, by all means go for it I'm just suggesting that those are not at the root of your problem.

Let us know if you find out more.

 

With the SCs its been shown that leaving the headlight switch in positon "ON" for a couple days without starting the car can kill the battery despite the automatic shutoff of the lights when the door is opened. Leaving the switch in "AUTO" is ok, I just remember to flip the switch to "OFF" everytime I put the car in park.

 

all very good questions

let's knock them down 1 at a time -
1 - the battery is in good health and is relatively new - it was put in about 2 years ago
2 - the coutesy lights are not left on accidently
3 - no aftermarket radios or lighting

Is there a simple way to check the voltage being put out from the alternator?


You've made some good suggestions.

 

interesting - as I do leave the light on "Auto" all the time even when I'm away for a few days. I will try the above suggestions and see what happens

 

Batteries can die in 2 years...thats not that "new", especially if its been discharged several times. That can kill a battery right there.

My radar detector shows the voltage of my system, the passport 8500, not saying buy one but I'm sure theres a way to check or plug in something that will tell you the voltage if nothing else than taking a voltmeter and putting it on the right ends. I get about 14.4 when the car is good and charged (And running), about 11-12.5 if the car is off. Your car should never be lower than 12.

You can also use this to check things that have a draw by turning certain things off and seeing if the voltage drops or goes up.

 

I definitely agree with above. One way you can check the output is to use a voltmeter directly on the battery terminals, both with the engine running and the engine off. With the engine running, I believe you should be reading 14-16. Another thing you can try is if you have a second vehicle, switch out the battery and see if you run into the same issue with the second vehicle, and vice versa. This way, you can possibly eliminate the battery as the source of your problem.

 

Be careful when switching batteries, since our cars use a reverse polarity set up.

And I'm entering my 3rd year with a $29 WalMart battery. It's not necessary to spend a lot (although those Optimas give you plenty of opportunities to do so).