Hello all,

My 05 LS430 decided (out of the blue) to downshift rather abruptly from 2nd to 1st a few days ago. Having done my research I knew this was fairly common and decided to take it to Lexus to see if the car needed the TSB TC006-04 applied.

Is it just me or does anyone else have anxiety when someone else works on their car? I asked for the master technician and explained the situation; ( its on air suspension and raised it to maximum height & removed the fuse so no one could mess around with it). The car has a celsior lip kit so please be very careful IF you have to put it on ramps to not damage it (previous dealership actually damaged the oem sideskirt). The trans had 3 drain/fills etc...

To be fair the mechanic was very friendly and could tell I knew what I was talking about.

From the start my options were:

Option 1: Have the TSB applied and fix the shifting issue.
Option 2: I remove the PCM, send it to SIA electronics to have it repaired (turns out its a 4 week wait - so that was a hard pass)
Option 3: Have the dealership send out the PCM to a local new contractor to get it "fixed".
Option 4: Lexus fit a brand new PCM and pair it with the immobiliser/key etc - estimated cost: over $2k

3 hours later here are the result:
Turns out my car did have the TSB applied to it from the previous owner, it was now throwing a transmission code due to the harsh shifting.





I decided we should try and fix the ECU - Left the car with lexus and got a call 4 days later saying that it was ready to be picked up.



Turns out they did fix it and the car has been running great!

This was just to let folks know that there is a contractor who works with Lexus (Smyrna) who can fix the rough transmission issue - I hope this helps anyone in the Atlanta Area.




TSB for those interested:


Thanks,
Yann