A little while back I made a post about our '19 IS300 all of the sudden throwing a ton of codes on start up (abs, power steering, blind spot, front camera, etc etc). First 2 times it came on it seemed to self heal in just a couple of minutes of killing the car and turning it back on. The 3rd time it came on it took me an hour to make it go away, had to pull the battery and fully drain the capacitors to do a 100% "soft reset".

The last time it came on it would not go away. Messed with various things over a few days and finally gave up and took it to lexus in hopes that they would troubleshoot and cover the issue under the powertrain warranty (only 40k miles on it now).

Before taking it in, i was able to pull a code using my cheap reader (P0500) for a vehicle speed sensor, but, there are a number of "vehicle speed sensors" , 3 of which are potentially inside of the transmission, so I decided to have them take a look themselves. Mechanic looked everything over and mentioned he was pulling a slightly more indepth code with his techstream scanner P050031 for a VSS. he also mentioned that he "cleared" the code and was unable to get it to come back on multiple test drives. He then concluded it was a "loose battery connection" which I know is not the case since the battery was beyond tight when the issue surfaced and it was me who failed to fully tighten the clamp when doing the last reset.

He did mention something about seeing "some history" of the front left abs sensor "not being happy" , whatever that's supposed to mean. They can't do anything else with it since the issue is currently not there so I'm picking the car back up. With the input I got for the front left abs sensor I decided to just order a new bearing assembly to throw in if the issue comes back up..... but then it got me thinking...

I know for a fact that with the issue present I am getting 0mph reading on the dash, so it certainly is related to the VSS. All the other system failures rely on vehicle and/or wheel speed to function, hence the codes, BUT the 4 times the issue has come up has ALWAYS been when getting in and starting the car. It was NEVER come up just randomly driving down the road... so it makes me think that the likelyhood of the ABS sensor just "not working" after literally working 10 minutes prior on a drive is not high, but this is probably more likely related to something else in the system.. according to
this, the signal goes from the "speed sensor" to the traction control ecu, then is converted and sent to the combination meter, and from there to the ECU : https://manualespurdy.cisdigital.com...05rwz006x.html


Can anybody do a sanity check for me for this logic walk..?

Also, can anyone possibly help confirm part number and location of the traction control ECU for the 2019 IS300? I'm stumbling across various part numbers and have gotten myself lost and confused after 3 days of searching and reading.

 

Pic of the hoopty in question … we did find out that the inside sidewall on the tires is completely obliterated (I’ll need to do some investigating) so while doing a new tire setup we’ll be switching up the wheels to a more street/pothole friendly setup .. going down to a square 18” setup instead of the current staggered 19s .. found a deal too cheap to pass on for some knock off wheels we’ll rock for a bit .. vors tr4 in a gunmetal finish .. got tired of the all black wheel look