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I would but I don't have my ECU, it is with SIA Electronics.
I called them today and they said the turn around time is 4 days even though the website says 2 days. Not happy about that.
Finding a good mechanic is hard I had taken it to two other shops and they told me it was the Transmission.
The interesting part is when they rebuild the transmission and you pick up your car and drive it and it still does the same thing...
Another thing to check are your negative (including ground points) and positive battery cables. (voltage drop)
Your transmission solenoid wiring harness pigtail may have a temperature (thermister) sensor (as does the A650-E transmission in 1998-2000 LS400) so if so equipped then perhaps this has an effect on shifting.
If ECU is not problem, then have whomever gave the advice issue credit in the amount of expenditure (if dealer then parts credit)
I am still waiting on my ECU. On their website it says "Units that are sent in for repair usually have a 1-2 day turn-around after being received ", which is total bull ****. They got my unit on 29th January 8.00am and today is February 6th and I got an email saying that they shipped it back today. I will update you on the outcome.
I am still waiting on my ECU. On their website it says "Units that are sent in for repair usually have a 1-2 day turn-around after being received ", which is total bull ****. They got my unit on 29th January 8.00am and today is February 6th and I got an email saying that they shipped it back today. I will update you on the outcome.
Sorry to hear you are still waiting for your ecu. Definitely keep us updated on the progress including if you replace the throttle position sensor.
The good news is that I finally got my ECU back today but the bad news is that it did NOT fix the problem.
This is my wife's car and I am in the dog house now. please help.
So back to what YODAONE was saying that it could be TPS.
I can NOT find Throttle Position Sensor for Lexus LS430 2005 ?
I can find a Acceleration Sensor (part number 89191-50020)
could it be the TRANSMISSION SPEED SENSOR 89411-50010 causing the issue?
YODAs post re the throttle position sensor is based on his LS400. https://www.clublexus.com/forums/ls-...-shifting.html
LS430's after 2003 do not use a TPS. Here's a pic of the TB on my '06 showing where the TPS would attach on earlier cars.
bradland thanks for clarifying that there is no TPS on a LS430 AFTER 2003.
So is it possible that it could it be the TRANSMISSION SPEED SENSOR causing the issue?
is there more than one sensor on the transmission?
Can these sensors be removed and cleaned? if yes then with what?
bradland thanks for clarifying that there is no TPS on a LS430 AFTER 2003.
So is it possible that it could it be the TRANSMISSION SPEED SENSOR causing the issue?
is there more than one sensor on the transmission?
Can these sensors be removed and cleaned? if yes then with what?
Anybody out there have any ideas please!
I don't believe the transmission speed sensors caused the harsh shifting from 2nd to 1st. However, if you want to remove, clean, and reinstall these sensors, here are the details (location, torque specs, etc.) for your reference...
bradland thanks for clarifying that there is no TPS on a LS430 AFTER 2003.
So is it possible that it could it be the TRANSMISSION SPEED SENSOR causing the issue?
is there more than one sensor on the transmission?
Can these sensors be removed and cleaned? if yes then with what?
Anybody out there have any ideas please!
I contacted Lexus for clarification on how the 2004-2006 ECU determines throttle position angle.
There is a Pedal Position Sensor 2001-2006.
The TPS is serviceablet hrough 2003,
Starting 2004 LS 430 used a different throtlle body altogether. but it still has an integral sensor to ascertain and communicate the opening angle of the throttle plate to the ECU....and TPS apparently is not a separate service item.
Perhaps someone could clarify and elaborate further.
The A761 Trans is EXTREMELY sensitive to incorrect fluid levels. Now that you know it's not the ECU, aka expensive potential fix, i would revert back to cheap and simple. Start with a basic drain and fill, which involves replacing 2 to 3 quarts, and replace with Toyota WS. The critical thing here is getting the new fluid level correct. It can be tricky, as your car does not utilize a trans dipstick, so it might be in your best interest to pay a professional to do the job. Your local Toyota dealer has the proper tools and I'd hope they won't try to sell you a new ECU like Lexus did?!?
Also VERY important- keep the drain and fill simple with just a few quarts. The main goal here is achieving a proper fluid level. Don't do all the fluid at once and definitely don't do any type of power flushing service. Hope this helps and keep us updated on the results.
The 2 speed sensors on the side of the trans are worth looking into but they are HARD to reach. Very tight fit where you need to get a hand and a tool at the same time.
This vid discussing proper fluid level and temperature is long (30+ min) but well worth your time...
01-31-18, 10:54 PM
