I have a 2006 Lexus LS 430. It has had a battery drain since new. The light switch is turned off, the proximity key is turned off. The battery drain is greater than 250 mA on my multi-meter. My meter is an old analog type; only goes to 250 mA. This drain has made it necessary to replace the battery every year since new. The Lexus dealer says it was just a bad year for too much electronics and says to drive it every day.

The auto trunk opener and the parking sensors don't work anymore.

Thanks,

William

1993 Lexus LS 400
2006 Lexus LS 430

 

Sounds Wierd your vehicle had had this problem sincee new. It had a draw and you will have to find it. You can keep your voltmeter connected to battery and pull fuses one by one until it shows 0 draw. Once you find what fuse it is, you would have to find a diagram of the circuit pertaining to that fuse and see what is drawing the power. Good luck.

 

I have to call BS on that dealer. I have an 06 that still has its same OEM Panasonic battery...9 years and counting. There is no issue with electrical systems on the 06 that I have ever heard other than sticky switches in mirrors and steering wheel controls. Did you buy it brand new?...Is there any 3rd party mod on the car at all, something like lojack, remote start, anything radio amp, or added or modified switches or wiring? 99% of the time its something like that on these cars and sometimes the owners were unaware of the mod. I'd also suspect trunk opener or parking sensor circuits - if there are no mods that is next place to look.

 

You could try pulling fuses and try to isolate the failing or failed component. Parasitic draw are not common on the LS430.

 

Jabberwock,

Thanks for replying. I really appreciate that. There are no aftermarket parts at all on the car. It has only ever been serviced at the Lexus of Calgary dealer. The car has all available options. I will try checking the circuits by pulling fuses. It is just that there are lots of them...

Do you think the TIS cable and software are a good idea for diagnosing and resetting codes for Lexi and Toyotas? It sounds like the best thing since sliced bread. I have 2 Lexi and 6 Toyotas. I have an 09 Matrix that has the VSC/ABS/Traction Control lights on and the Traction control is turned off. Been that way for a year. Sounds like this software could help.

Thanks,

William

2006 Lexus LS 430
1993 Lexus LS 400
1993 Celica ST
1992 Tercel
1998 Avalon
1997 Camry
2009 Matrix XR
2003 Matrix XRS
2002 Highlander

 

Lavrishevo,

Thanks so much for replying. I wanted to ask you about buying the cable and software for TIS diagnoses. Do you think it is a good idea. It sounds like the best thing since sliced bread!

Do you think the TIS cable and software are a good idea for diagnosing and resetting codes for Lexi and Toyotas? It sounds like the best thing since sliced bread. I have 2 Lexi and 6 Toyotas. I have an 09 Matrix that has the VSC/ABS/Traction Control lights on and the Traction control is turned off by the computer. Been that way for a year. Sounds like this software could help. I live in Canada where we need Traction control 6 months of the year for ice and snow.

Thanks,

William

2006 Lexus LS 430
1993 Lexus LS 400
1993 Celica ST
1992 Tercel
1998 Avalon
1997 Camry
2009 Matrix XR
2003 Matrix XRS
2002 Highlander

 

Lexus and Scion are made by Toyota. You probably know this. So yes, all 96 and above Techstream is the ideal diagnostic tool. I think you may be able to use the adapter for 96 and below OBD1 as well but I am not positive it works.

http://www.ebay.com/itm/For-Toyota-17-pin-OBD1-to-OBD2-convert-Adapter-Code-Reader-Diagnostic-Scan-Tool-/221265640595?hash=item338475bc93&item=221265640595&pt=Motors_Automotive_Tools&vxp=mtr

 

fastwill, just be aware that it takes some amount of time for all of the many electronics to go to 'sleep'. I do not know the exact times but I would wait at least 30 minutes before going on the witch hunt (pulling fuses).

btw, awesome info, rkw!

 

I noticed he was in Canada. Are there any other systems in the Canadian spec LS?

 

Thanks so much to all of you! I will let you know what happens. I know for sure the lights in the trunk are shutting off now. I will try to locate the drain by pulling fuses.

Thanks,

William

 

fastwill have you had any luck? This may not help, but in my'92 soarer there is a little light in the glove box that always stays on... no idea why. So i just pulled out the bulb and now its okay.

PS: Where in alberta are you? im in red deer.

 

Just testing today. And Calgary

 

Here's a decent video how to check for a "parasitic drain":


Unfortunately this car has a lot of fuses, but it should work.

Eric has some good videos and a pretty active website for problems like this.