Check Engine & Traction Control Warning Lights
 

Hi,
I have an intermittent problem with the check engine light and traction control warning lights coming on and staying on simultaneously for no apparent reason. When my mechanic pulls the codes it reads, "Internal Transmission Temperature Sensor". He had just serviced the transmission as the car is high mileage with 253,000 miles on it and the transmission is functioning properly. The lights go out after many start cycles have have been completed, but the lights come back on in a few days and then go out again after many start cycles and this continues to happen. My mechanic told me we should try replacing the internal temperature sensor and when I called my local Lexus parts to order the part he told me I had to bring the car into their service department. Has anyone seen this before? The transmission shifts and functions as normal and the transmission fluid and filter were changed twice as the old fluid was dark and dirty. Did the fluid change cause the problem? I'm reluctant to bring my car to the dealers and these warning lights keep coming on every few days and then it resets itself and they go out, only to come on again a few days later. Any information and advice will be greatly appreciated as I am driving Uber and this car will see 300,000 miles soon and is going strong with the original engine and trans performing like new.
Thanks :thumbup:,
Neil

If your mechanic serviced your transmission, he should be able to diagnose/replace the faulty part instead of the dealer?
Lexus should be able to sell you the part, maybe they need your car in so they can read the VIN, but you're within your rights to order the part blind without requiring any additional services.

Did you talk to the parts department or the service department? Often separate entities at the dealership. If they still give you the runaround I would try a different dealer.

They need my car to read a VIN? They wouldn't trust me to give it to them? That would not surprise me. My local mechanic services all makes and models and I know they do not have a clue there on this particular problem with my Lexus. They go online all the time to figure out how to proceed when it is new to them. The boss there is all too eager to replace parts, hoping he guessed right (as he is not paying for the parts, the customer is) and that if he throws enough **** against the wall, some of it is bound to stick. When the transmission pan was off, could he have taken a voltage or ohm reading at the inside temperature sensor to test the sensor to diagnose the problem? After 2 transfusions and filters and fluid it would take a third time to get in there to change that sensor and considering the cost of the parts and additional labor, why bother? What purpose does this sensor serve anyway? The transmission is performing as new. If this does not effect the performance or life of the transmission these lights can cycle on and off and it doesn't mean anything except Lexus making something simple very complicated. For example: Lexus ripped me off changing 3 tire pressure monitoring sensors. Their sensors have to be programmed by their dealer as they are the only ones that have the electronic tool to program them, prior to installation. They charged $85 for the programming, $50 per wheel and $150 per sensor. It cost me over $500 to R&R 3 sensors! I love the car but hate being set up and ****ed over paying an extremely high price $500 for an easy job that should have cost $100. I asked the service advisor if that price included the Vaseline so it wouldn't hurt so bad. He understood what I meant. If it isn't the dealer screwing their customers, it's the privately owned repair shop, both know they have the guy by the balls as he knows little to nothing about what they are working on. My guy can replace the part at a more reasonable price but I don't trust him making the correct diagnosis. I did see the trouble codes and it did show that sensor. I may try another Lexus parts dealer like Bell Lexus in Scottsdale, AZ where I buy my parts as they have the lowest prices and are helpful, unlike my local dealer where they are crooked. I find it really dumb to design a transmission with no filler tube to check the level and putting the filler plug in a very difficult place to access and then they do not put in a sensor to warn about low fluid level, yet they needed a temperature sensor! WTF??!!
Thanks anyway,
Neil :wild:
Thanks

Sounds like you need a new local mechanic. Anyone who knows Toyotas should be able to work on the ES350 as it is basically a rebadged Camry V6. The power train is exactly the same.

I feel for you and wish you luck.

I would go back to your original mechanic shop and complain at the top of your voice how, after the transmission service, you got this light so they must have broken something, or they must not have filled it up right to set the sensor off. It should be their responsibility to investigate and set right at no additional cost to you. After this, start looking for a new mechanic that has experience with Japanese cars.

I wouldn't ignore it, if the transmission gets too hot then stuff will break or seals will leak.

You need a transmission specialty shop or a better independent foreign car or Toyota specialty shop. Stop going to the dealer and getting robbed.
Use this link to hunt for shops recommended by listeners of the Car Talk Radio Show
https://www.cartalk.com/mechanics-files

then cross check any candidates with Google or Yelp as some reviews are old.

You can find many online sources of Aisin Warner U660e Transmission parts with a simple search.

However, since it runs okay, with that many miles I would consider not throwing money at it and just driving it the way it is until it dies. Save your money for a replacement. Odds are once you throw a small fortune at the transmission something else even more expensive will break and you will regret having spent the money. Realize the rest of the vehicle is also a ticking bomb of parts failures since you are approaching 300,000 miles.

Finally how old is your battery? Low voltage from a weak battery will make random warning lights appear. Get it tested at Auto Zone etc.