corradoMR2

Today, I fell victim to a dead battery in our RX. It's my fault since I left the rear hatch open all night, plus factor in crazy cold -15C weather and you're toast (or popsicle in this case). I still am puzzled as to why the drain since lights turn off after a few minutes so I'm open to comments on this since there should be a fail safe mechanism to prevent such a drain.

Of course, this morning, trying to start the car, the RX reacts like you're torturing it spewing all sorts of errors and the starter making that ticking noise.

After I boosted the car with my IS and started the RX without issue, I expected the TRAC OFF, Check engine light, etc to be off, but they are still on. Even after driving the car for 30 minutes to charge the battery, same thing. Car drives normally and in fact, traction control kicked in when taking off on snowy ground. (Possibly TRAC OFF implies VDIM is off in this case, not sure). There's no "reset" procedure to my knowledge, at least not in the manual. I also searched this forum, found some drained battery threads but none mentioned the errors. Any comments? Thanks!

kitlz

Ouch corrado. What did you do? I'm not aware of any fail safe mechanism for the lights other than the headlights. Nor have I turned off VDIM to know what pops up on the dash. Might be time to head to the dealer and make sure the tailgate is closed from now on. Even better, hit the button in the glove compartment to disable it. Good luck and stay warm.

m1964

Once I drained the battery by listening to the radio and charging my laptop - when trying to start it would not turn, I then waited a minute and tried again - it started, and had same lights ON as yours. After driving for one day lights went off.
If it drives fine, wait a couple of days - if the lights are still on, disconnect the battery for 3- 5 min. and see if that clears the memory.

corradoMR2

Thankfully I didn't have to go top the dealer, I figured it out.

I spent the last hour+ troubleshooting and got it to work. I figured a "reboot" is what's needed and will probably only occur if I disconnected the battery. I did just that, waited 20 minutes, re-connected and that did the trick! I then drove around 30 minutes or so to charge up the battery. I now see your post about disconnecting the battery so I'm confident it's fixed. Thanks for the post.

vlad_a

Anita,

Lexus put fail-safes EVERYWHERE in the 2013+ RX. Every single light is on a timer. Even the ACC mode is on a timer, which is a bummer trying to work on the car and listening to the stereo. The downside is also that the auto lights off only works in the Auto mode. If you leave the parking lights or headlights on, it will buzz at you like a 20 year old Camry and will keep them on, until the fail-safe timer triggers.

kitlz

Wasn't aware they made that change. Maybe the extreme cold was a factor At least corrado got rid of the warning lights and is ok for now.

oohpapi44

iTrader: (1)

Pulling the ECU main fuse for 20 mins will also reset the computer.

corradoMR2

It's what I thought but echoing Anita, if this was the case, why was the battery drained? Headlights are set to Auto and I know they went off because I had initially closed all doors and locked the car. I then went back out to open the hatch, get stuff out, and left it slightly opened. Car was of course left unlocked so no alarm was running to drain battery power so what other system(s) was running that drained the battery? .

Good to know for the next time

vlad_a

That's not normal on 2 levels. First off, your lights should have turned off. If the hatch is open, eventually only the small red light will remain lit up on the speedometer. Second, the battery should not be drained by the light in the back. It should survive up to a full day, if it is in a good shape. My kids leave doors ajar all the time, and sometimes leave the dome light on. The RX just tuns them off and keeps going about its business.

corradoMR2

^ ^ ^ what I suspect is the multiple short trips (5 Mins) my wife did with the car the prior few days combined with the frigid temps weakend the battery's capacity.

cflutist

This is all good information. Thank you all for posting.

ggebhardt

^^^This^^^

Hard to believe that a simple light drained the battery to dead. The Lexus should have turned it off after a period of time but even if it did not, the tiny bulb should not have killed the battery, even in the cold.

DunWkg

I was thinking there are three lights in the back storage area, the two sides and one on the lift gate and the two sides stay on and the one on the lift gate auto turns off. Still, even if true, wouldn't think those lights would drain the battery overnight.

FamilyRX

Just one of the courtesy light bulbs can draw 0.5 amps which is enough to drain a battery overnight. Before cars used to have the logic to automatically turn off lamps that were left on, we used to see vehicles get towed in for leaving lights on especially in mini vans and SUVs (kids in the back row playing with the lights).

tfischer

Another way to prevent a dead battery from an overnight open door or hatch is to replace the lamps with LEDs. These are far brighter and whiter, and provide great illumination and at the same time, as if by magic, draw very little power. I left the hatch open overnight somehow recently in my '04 RX; in the morning the lights were burning bright, but the car started up right away. (Before changing the lights over, I also ran down a battery when a door on my SC did not close tightly one evening.)
The battery issue is perhaps not the best reason to make this change, which can get a little expensive, but it is a nice side effect. The real reason is the bright illumination - a few weeks ago a friend helped me carry some things to load into the back of the RX in the evening, and when the hatch opened up, he mentioned the lights right away. He assumed is was a Lexus thing, so I told him I made that change, and informed him he could, too. For starters, I would suggest doing this for the trunk space in a sedan or the rear space in an SUV, as that is where you use the extra illumination most often. (Then move to the overhead lights in the front seat.)
Finally, it's a little costly, but I saved all the original lamps, and will replace them when I sell the cars, as many of the LEDs will surely fit into whatever I get as a replacement.