I have a 2003 ES300 with 149K miles that just threw a code P0128 which the Auto Zone tech said it meant the temperature controller can not regulate the temperature because the coolant temp is too low. So, he suggested either the thermostat is bad or going bad or the coolant temp sensor is bad. Does anyone out there have any thoughts on this ? I looked for the thermostat and couldn't locate it. Too used to old American muscle cars. I'm sure they must have it buried under there somewhere. Also, any idea what Lexus would get to change out the thermostat ? While I have no problem changing the oil/filter, when it comes to pulling things apart these days and leaning over the fenders, my back would not permit it due a moron rear ending me back in 2000. Even with surgery it has never been right since, which limits what I can do. Thanks guys !!

Read the following post
https://www.clublexus.com/forums/es-...004-p0128.html

Ask the original poster if the thermostat fixed his p0128 code