Suddenly, this happened with my 2004 LS430 at just 103,000 miles:
1. driver's side temperature control stuck in "dual" mode, up/down works ok.
2. Passenger side control stuck on HOT.
3. VSC light came on. Trac.control button inoperative.
4. Check engine light came on.
Car runs well. Is this all related? Will dealer take hours to find this? What to do?

Thanks!

 

I'd start by hooking up an OBD2 scanner and pull the code related to #4 (Check Engine Light). That and #3 (VSC) are directly related. Correct the cause of the Check engine light and the VSC light will extinguish as well.

Items #1 & 2 are also directly related. Try removing the passenger side temperature switch and see if that will release the "dual" light on the driver's side. There have been incidents of owners having issues with the temperature switch (not that common but there are a few threads), and it's apparently rather simple to remove. Here's the link to the DIY.... Temperature Control Linky

Let us know what you find!!!

 

Local mechanic did the code check and they said these all came back as bad:
CAT BANK 2
ENG Immobilizer
Eng ground fault
front airbag sensor right and left
steering pad switch
front light ecu comm stop
solar sensor
max cool damper pos

He said the passenger temp control is bad and needs to be replaced for $167 (says there are only 4 left in the USA?).
Also says the right catalytic converter is bad (per the code reader) and needs to be replaced for $1,400 (with a $1,100 deposit first); Also suggested the left one could go soon.

Meanwhile, the car at 103,200 seems to be running just fine. He's suggesting I get rid of it ASAP. I haven't even put the snow tires on yet.

Could this be a massive misdiagnosis?

Is there a universal cat converter I can substitute in New York State?

I'm not a mechanic. So what would you do?

 

I would be suspicious of the catalyst bank 2 failure code. Many LS430s experience the P0420 and P0430 codes (left and right side catalyst efficiency low), but this is due to near-invisible cracks in the Y-pipe or failed Y-pipe gaskets.

Solar sensors (2 front and 1 rear) are not bad, it throws failure codes if you don't shine a bright light at them during the test.

It sounds like an electrical issue caused the other codes. Maybe someone power-washed the engine bay or water got somewhere it shouldn't have, causing cascading failures. I would start at checking the engine ground fault and ECU wiring.

Post the exact code numbers and we can provide the proper diagnostic steps (and you can also search these for the codes on these forums and likely find solutions). Or take it to an LS430 specialist if you aren't very hands-on.

 

How many miles before 103,000 did you own the car? Wondering if you bought it at 102,750 and you got all the codes at 103,000 or you've owned it since 50,000 and now received all the codes?

If you've owned the LS for more than a thousand miles or more, did you recently do anything in the engine bay? Similar to what Stan is wondering, like power wash the engine bay?

I also agree with Stan to get the NUMBER associated with each code. Now might be the time to buy a decent OBD2 scanner! You can also clear codes with the scanner too.

The code associated with the catalytic converter is probably NOT a bad cat, but a leak/hole somewhere in your exhaust pipe. I experienced the same code and thought the same thing, that a cat was bad, but when viewing my exhaust while car was on a lift, the front Y-pipe had several rust holes. I bought the pipe for about $600 (it was genuine Toy/Lex Y-pipe) and had a buddy with a lift do the work. It was very easy for even a semi-skilled mechanic to replace, assuming they have a lift.

Since you say the car seems to drive fine currently, I personally would buy an OBD2 scanner (it ALWAYS comes in handy), scan the codes, document them, then CLEAR them, and drive the car for a couple days and see what comes back after several days of driving.

One thing you do NOT do is continue to drive the car if the Check Engine light is FLASHING. Flashing=really bad misfire or something that will burn up your cats, and like you've been quoted, cats are big money.

 

Really appreciate the guidance so far! I bought the car from a dealer in October 2011 with just 25,000 miles on it (I verified that!).
I did nothing to the engine bay. No big puddles or snow.

Here are the exact codes:
CAT BANK 2 PO430
ENG Immobilizer B2799
Eng ground fault C1201
front airbag sensor right and left B1615 and B1610
steering pad switch B1285
front light ecu comm stop B1296
solar sensor B1424 B1421
max cool damper pos B1434
sensor cir r B1435
Undocumented B1435

Based on your ideas about the cat, should I take it to a muffler specialist first?

Thank you!

 

i found my cats on amazon for a lot cheaper. and they were bosal converters. bought both of my converters for just under $300. i ended up ordering gaskets from Lexus b/c everything i found aftermarket didn't appear correct.

 

What would I do? I would buy a OBD2 reader, clear the codes, then see what comes back. Hopefully nothing, but inevitably, being that you're in NY and they salt the roads which accelerate corrosion and rust, I'd predict your P0430 will come back, because I'm going to guess, like the rest of us have experienced between 100k-150k, there's a hole/leak in your front Y-pipe.

In addition to clearing the codes with an OBD2 reader (or disconnecting the battery), you need to drive the car for several days to see if/what code(s) come back.

The link discussing the Y-pipe and P0430 code can be read here... Good linky to read about P0430 code

 

Number one... get an OBD bluetooth plug in. Then download the Torque App or something similar. You'll need this.
Find it very hard to believe that car with only 25k miles on it is having cat issues... does not make sense.

As for things the dash going crazy... from my experience... this could be an electrical problem. These cars highly sensored/computerized. Any glitch or problems with the power will cause the sensors to send a code or even force the car into limp mode. Your 'multiple' issues all at one time leads me to a common source instead of all of these things going bad at the same time. I'd clear all the codes and start over paying close attention to the cars handling.

The only caveat to that is if the is a rebuilt/salvage car then there's not telling what is wrong with the car. Good luck.

 

Hi Legend - Your ideas make sense, I'll give them a try. Also, to clarify, I bought the car at 25K miles about 8 years ago - it now has 103K on it. It's been great mechanically up until now. Will keep you all posted. Jonathan

 

Also you might want to check or replace your battery if it's old. Weak batteries tend to create all kinds of problems on LS cars.

 

So I replaced the passenger-side temp. control successfully. Then I took the car to a Midas muffler franchise (yes, really). He reset all the codes and the code for the right side catalytic converter came on. He also made note I've never tuned up the car since I got it 6 years ago. I got the new cat, new plugs, 02 sensors, air filter, cabin filter, oil change and $1,400 later drove it home. When the snow stops tomorrow I'll take her on the highway and see what happens. So far, so good.

 

I know this is vague, but look at the battery - it may have weird intermittent issues if its over x years old. If weird electrical things persist, buying a fresh battery before its DEAD certainly isnt a waste of money.

 

Battery is in very good condition. Thanks.