XRX

In terms of warranty, I would buy OEM from Lexus/Toyota dealer (having old battery with you or bring it later).
PS: I had brand new 12v from Lexus dealer and didn't have any issue for next 5 years, but then I drained the battery by leaving OBD reader in parked for 2 weeks car.

JoeyP123

Worried about what. Did he get to close

joedaddy1

iTrader: (1)

It sounds like you've changed the battery, recently. Now, I would get the codes read again.
I think everyone is just throwing guesses here.
Could be a disconnected plug, a wet/flooded wire/electronics, just 1000 reason.

FYI.. you battery shouldn't go down to 11.7v overnight. It seems like there's a electrical drain that's not normal.
Do you have dashcam / remote starter / aftermarket radio / heck maybe even a GPS device that's draining your battery?
Also, getting a $15 OBD reader will allow you to see the charging voltage to your 12v battery.
My 12v battery stays around ~12.4v overnight, i believe.

Again, I'm not a mechanic.. Just a guy on the internet with a keyboard.

pakris

I do sense what you say about an electrical drain.
No after-market extras and I don't use the auxiliary items because of the sensitivity. Something that got wet from the weather causing extra humidity is possible along with the lightning and atmospheric changes we had. May sound silly to techs but when it's happened before with the same conditions, well ya just know. Plus all of the codes have a lost communication msg in common. 12v change was the first right fix!

No coincidence that my outdoor A/C unit went into a high or low pressure lock out the same time. That, thankfully, took a tech a few minutes to adjust the pressure and tap a relay switch. He let me watch it all and everything else tested normal.

I'm getting the OBD reader. It looks good and I would never know to find that one. I clicked the link and it is still on sale but 19.00 for me. Not a big deal. And thank you for clarifying getting new codes now after the new battery is in.

pakris

I already returned the Optima battery that was failing and replaced it with a Diehard AGM similar specs CCA etc. (not an acid one).

And you're right about driving/starting everyday. The Hybrid does charge full just sitting in the driveway after starting now. Plus all lights are just a bit brighter which makes sense.
I just can't drive it long enough (less than a mile), w/o the VSC light coming on.
Now to find what part or wiring is failing in the engine area.

Someone else had replied on one of my two recent post about 12v fans in the back seat that he changed out. That was because of the one BUS code I think. That was captured with the old battery and yes a fan came on briefly but did not come on after disconnecting and reconnecting the old failing 12.v to start the car and pull into the parkinglot at Advanced Auto.

pakris

Years ago when I had a drained battery a 'Mechanic' told me I couldn't change the 12v myself. So back then I was concerned. Yeah there are people like that out there and that is where my car was towed to (his shop).
So, I got on this forum and just wow. What a liar he was to me.
I changed it then after advice from this board and I changed it again this past week! LOL live and learn.

I'm thankful for those who helped me then and got my car running plus the correct education.

XRX

How often do you hear the hybrid battery fans under the rear seats? Have you inspected the vents under the rear seats? Point 2: https://www.clublexus.com/forums/hyb...l#post11613932
In normal operation, the vents are ON when it's really hot outside (90F+) and car is parked.
A/C ON + AUTO climate control mode are able to cool the hybrid battery well while driving or parking in shade.

pakris

Good question. I don't hear them. Only recently and once (where the BUS code was captured) did I here a fan in the back seat when the warning lights came on. I don't hear them now at all.

Only when I disconnect the neg side battery for less than a minute I hear to the upper left of where the 12v is a kind of buzzing sound for 10 seconds and then a little shorter 5 seconds when it's reconnected.

I don't use the A/C or Heater now and haven't for this past year.

pakris

Well, I got the scanner from the link and I should have read more of the description on amazon as it does not support my 2006 RX400h. I plugged it in for setup after reading the instructions and it didn't find VIN. So, any suggestions on an OBD car diagnostic for my car that will read and remove codes?

Strlsn

@pakris I think it was @XRX who suggested the Nexas Nexlink OBDii/EOBD Diagnostic Interface scanner to me - I haven't used it yet, but I'll attach the Amazon link

NEXAS NexLink OBD2 Scanner...

pakris

Thank you! @Strlsn and @XRX . I'm In the process of getting it now.

One strange thing that happened even though no codes were scanned is that when I touched ok clear codes I saw the VSC light turn off. lol
Oh boy. The Hybrid icon on display was full but I'll wait for more diagnostics because it could come on again. Also found a video about removing and cleaning the 3 vent covers/filters under the back seats. Never knew that was something to regularly check. I'll share a picture when I do that. There are two clip covers on each side of the vents that you can use a small flat head to open and then remove a 10mm? bolt/screw and they come right off. Seems like that should be in the manual. But I found the video anyway.

Patricia

joedaddy1

iTrader: (1)

did you try connecting it while the car key was in the "ON" position? You don't have to start the engine (you could, but you don't have to).
Also, you can try a different brand, even a bluetooth OBD. They are all the same. All made in china with cheapest part possible.
Did it specifically say "this item does not support 2006 RX400h?" maybe it did, but I highly doubt it. Nothing special about our cars vs any average car on the road.

Anyhow, make sure the car is "ON" when you are reading codes.
Good luck and wait until the VSC light turns on again and then read the code before clearing.

pakris

Hey @joedaddy1 , Yeah the description does specifically note under "About this item" in 2nd paragraph ......Please note that it is not suitable for new energy or hybrid vehicles.
But I replaced it with a Nexas NL101 and will post the results separately. TY

pakris

Ignition on no warning lights.

Warning light came on midway through this display while driving down my street.

Could a leak in the evaporator system cause high temperature in coolant?