iewiew

I parked yesterday for about 2 hours and when i returned the car was completely dead. I got a jump start, the insta nt we connected the car instantly came back to life. This moRning all was well. I took it to the dealer and had it checked out. The battery was 100%nand all systems were ok. What the heck is going on? Have any of you experienced this?

jmcraney

What you described is what would happen if you accidentally left the car with the ignition on (engine not running). Your car is equipped with a feature that warns you when you are leaving the car with the ignition on, if you take the key with you.

iewiew

That is a possibility! Lexus shure does'nt know!

jmcraney

Well, you came to the right place. We know some things here that Lexus doesn't know.

Some of the car's have defective doorjamb switches and that compromises the feature that warns about the ignition left on. It's easy to test - just leave the ignition on, with the engine off (by depressing the Start button twice without your foot on the brake). You should hear the warning tone from the external sounder - it's located near the left front wheel well - if you leave the car and take the wireless remote key with you.

whitewater

I had this happen 3 weeks ago. took to lexus. everything checked out (battery, alternator, no draw, etc...). only thing I can figure was I left the sun roof open in the garage and some how it drained the battery.

jmcraney

The thing that told us that the ignition was left on in lewiew's case was he said "I got a jump start, the instant we connected the car instantly came back to life." That was a strong indication that the ignition was on when the battery was discharged and was still on when the jump connection was made - that's the way these cars work.

In your case it is unlikely that the sun roof had anything to do with your discharged battery.

Since your event happened in a garage, the most likely cause is a defective doorjamb switch on the driver's door. Defective doorjamb switches on these cars are very common and among the many problems that they cause is the failure of the headlights to auto-extinguish after the ignition is turned off. We have discussed this issue extensively in this forum.

And that's another thing that we know and Lexus doesn't seem to know.

whitewater

that is good to know. that syncs up with my experience from a couple days before where my head lights did not turn off till I locked/unlocked & opened the door.

i'll check the drivers door switch as I had a similar issue on my LX 450 several years back.

Thanks!

roadfrog

That sounds like normal operation. When you lock your doors with the remote, the lights will stay on for a period of time and then turn off. If you press the lock button a second time, the lights go out.

jmcraney

Normal operation is for the headlights to go off automatically after a delay period that begins when at least one door is opened followed by all doors and trunk closed. Locking has nothing to do with this delay. You can truncate the delay by operating the LOCK button twice on the wireless remote key. If the doorjamb switch is defective such that no doors are sensed open, then the delay period will not start and the wireless remote key will not extinguish the headlights in response to the double-LOCK operation.

enoch861

Also if a doorjab switch is defective and you try to lock the car using the keyfob it should have a constant high pitched sound that lasts for about 10-15 or so seconds I would imagine since that's what happens when a door isn't closed.

jmcraney

The car will lock normally with the wireless remote key even when the doorjamb switch is defective in the most common failure mode which is such that the doorjamb switch never senses that the door is open. If you try to extinguish the headlights with the double-LOCK operation when the doorjamb switch is defective the lights will not extinguish and there is no warning tone.