Hello. This is 2006 rx330 awd. Dealer read codes and came back with "torque converter clutch stuck off".
Research shows other maker owners (e.g. little older cadillac) having this problem and just ignoring it. At most it comes to lower mpg, some say.
Dealer that read the code, and checked the car, recommends replacing the transmission (I am taking the dealer's recommendation at a face value, so far I have no reason to trust/run away from- this dealer).
Thank you.

 

Welcome to Club Lexus.

Believe that is the first we are seeing of that error code here. Have you had the vehicle since new and have you had the transmission fluid changed previous? Did the dealer clear the error code and does it come back? If they did not clear the error, I would take your RX to an AutoZone or Advance Auto Parts and ask them to read the error codes for you and to clear if possible. They usually do this for free.

Should you want a second opinion you might take your RX to a local Toyota shop to see what they have to say.

If the transmission has to be replaced and at the moment it is working fine I would just drive it until it starts giving you bigger problems while debugging this matter.

 

Why should it need a whole transmission over that? Older GM vehicles had this happen all the time. It was just a switch in the side cover had to be replaced.

 

The problem I am aware of with the GM transmissions was with a vacuum assist module that would always seem to go bad. Not sure if that is the same as what you are referring to but it sounds close.

 

I guess you are beyond the 6 year 70k miles Lexus Powertrain Warranty?

 

The car's over 80k miles. Warranty's long over. Actually, this car is my cousin's. She asked me if I knew any other repair shop than the dealer.
PO741's one possible cause may be faulty torque converter solenoid valve buried (presumed) in the transmission. One advice (not this forum, not this car) was replacing the trans may be an option since getting at this valve is expensive anyway.
The dealer's diagnosis was paid for, but at $130, I doubt they checked the wires (short or poor connectors being one cause).
I assume PCM (ECM?) is working since the codes were read.
For all I know from the short research, it may be PCM ground issue or low fluid.
It is just that one poster elsewhere said that with the faulty TCC solenoid, the TCC will lock up at around 50 mph and the effect is basically lower mpg. Some others have ignored this cel and kept on driving their cars.
So I am wondering if ignoring it applies to Lexus?
Thank you for the interest.

 

I have a 96 camry (daily beater) with the solenoid problem: the CEL is on constantly....I just ignore it and keep driving.....

someone said seafoam works but I havent tried that yet......

http://www.seafoamsales.com/trans-tune-faq.html

 

Could be a piston in the valve body is hung up....A good tranny shop could drop the valve body assembly and clean it and re-install. I would not do a flush....Changing the filter and fluid maybe with something like AMSOIL might be worth a try. Those shift solenoids onthe RX300 are servicable, not sure on the RX330 tranny....