P0761 on 2005 LS430
Thread Starter
Driver School Candidate
Joined: Oct 2025
Posts: 23
Likes: 3
P0761 on 2005 LS430
Needing some ideas or help.
Getting a P0761 code on the first drive of the day.
I have found that I can clear the code while driving and it’s happening and it will immediately shift just fine for the rest of the day. I can also turn the car off and back on and the symptom goes away for the rest of the day.
I’ve already replaced the S3 solenoid, added new fluid, and new filter. It drove fine after the replacement. But let it sit overnight and it’s back to doing it on the first drive again.
I’ve also sent my ECM to TechnicalDomain and he claimed he made some repairs but, who knows on that.
Issue still remains. Any ideas? I’m not getting any other codes.
Getting a P0761 code on the first drive of the day.
I have found that I can clear the code while driving and it’s happening and it will immediately shift just fine for the rest of the day. I can also turn the car off and back on and the symptom goes away for the rest of the day.
I’ve already replaced the S3 solenoid, added new fluid, and new filter. It drove fine after the replacement. But let it sit overnight and it’s back to doing it on the first drive again.
I’ve also sent my ECM to TechnicalDomain and he claimed he made some repairs but, who knows on that.
Issue still remains. Any ideas? I’m not getting any other codes.
Last edited by jxke; Oct 26, 2025 at 04:44 AM.
Racer
Joined: May 2017
Posts: 1,525
Likes: 354
From: Utah
Claims he “made some repairs”?? Did he replace all the capacitors in your ECU? Or not? It’s probably got a leaky capacitor if it shifts when u reset the codes like that. I would send it to one of the other companies that rebuilds them, have them put the performance tune it too, I swear it adds 50hp to the later 3UZ’s.
Thread Starter
Driver School Candidate
Joined: Oct 2025
Posts: 23
Likes: 3
Claims he “made some repairs”?? Did he replace all the capacitors in your ECU? Or not? It’s probably got a leaky capacitor if it shifts when u reset the codes like that. I would send it to one of the other companies that rebuilds them, have them put the performance tune it too, I swear it adds 50hp to the later 3UZ’s.
I went ahead and changed the Speed Sensor on the transmission this morning and reset transmission memory with my scan tool. Guess I’ll see if that makes any difference tomorrow morning. Right now it’s shifting beautifully as usual. Only happens after sitting overnight.
CL Community Team
Joined: Dec 2005
Posts: 2,697
Likes: 824
From: 565 St Peter NOLA
Early, pre VVTi, LS400’s we’re plagued by leaking capacitors.
It was addressed well before 430’s were introduced.
I’m not saying it couldn’t happen to a 430 but it would be rare.
Bad solder joints, yes, leaking caps, not likely.
It was addressed well before 430’s were introduced.
I’m not saying it couldn’t happen to a 430 but it would be rare.
Bad solder joints, yes, leaking caps, not likely.
100% correct some 430's had issues due to cold soldering I believe. Never heard of any issues with capacitors as you stated incredibly rare to the point I have never heard of it happening
Racer
Joined: Jan 2004
Posts: 1,889
Likes: 456
From: North Carolina
If still acts up try this. Put a trickle charger on battery when car off for the day until need in morning. This will discount the battery that has been know to cause numerous problems with transmission even if cranks fine.
Trending Topics
Thread Starter
Driver School Candidate
Joined: Oct 2025
Posts: 23
Likes: 3
I’ll give it a shot. Highly doubt it’s that though.
ClubLexus Stories
Celebrating Lexus & Toyota from Around the Globe
Top 10 Lexus & Toyotas to Drive Before You Die!
Joe Kucinski
Top 10 Lexus/Toyotas With The LEAST 5-Year Depreciation
Joe Kucinski
Lexus LC500 Convertible Auction: A Preview of Rising Values?
Brett Foote
GX 550 vs TX 550: Best 3-Row Luxury Lexus Family Hauler
Michael S. Palmer
9 Best Lexus Models You Can Buy for Half Price (And 1 You Shouldn't!)
Joe Kucinski
2026 Lexus NX Buyer's Guide: Models, Features, Prices & More!
Brett Foote
Top 10 Reasons to Buy a Lexus TX 550h+ (& 3 Reasons to AVOID!)
Michael S. Palmer
Top 10 Lexus & Toyota Models of the 1990s RANKED!
Joe Kucinski
10 Great Toyotas That Could Have Been Lexus Models
Joe Kucinski
Thread Starter
Driver School Candidate
Joined: Oct 2025
Posts: 23
Likes: 3
It seems electrical. I just don’t know where since the ECM was supposedly repaired by TechnicalDomain and the S3 solenoid is brand new.
Last edited by jxke; Oct 25, 2025 at 04:01 PM.
CL Community Team
Joined: Aug 2011
Posts: 4,168
Likes: 1,006
From: Japan
Sounds like the valve body line is blocked by foreign objects such as the clutch dust and etc. You probably need to clean it. Sometimes changing the ATF several times may fix it. It sure takes time to be OK.
No, because as soon as I clear the code while driving and it’s stuck in 3rd it immediately shifts to 4th. This is on first drive within a few minutes and the engines still cold.
It seems electrical. I just don’t know where since the ECM was supposedly repaired by TechnicalDomain and the S3 solenoid is brand new.
It seems electrical. I just don’t know where since the ECM was supposedly repaired by TechnicalDomain and the S3 solenoid is brand new.
By clearing the code you are manually overriding whatever failsafe the car is doing.
Last edited by 05ls430518; Oct 25, 2025 at 05:41 PM.
Racer
Joined: May 2017
Posts: 1,525
Likes: 354
From: Utah
Any ECU that uses electrolytic capacitors needs to be serviced by the time they are 20 years old. Lexus kept using the same capacitors long after the 3UZ. So the ECU is certainly a potential culprit, seems like the first symptom is usually related to the transmission. Your first post made it sound like the ECU had not been properly serviced, that’s why i assumed it was a good place to start, often there will be signs of a problem when you look at the circuit board but certainly not always. Anyway sounds like you have a couple places to start doing a diagnosis
Thread Starter
Driver School Candidate
Joined: Oct 2025
Posts: 23
Likes: 3
Restarting the car has the same result. It shifts fine for any trip I make for the rest of the day as if there’s no issues.
Racer
Joined: Jan 2004
Posts: 1,889
Likes: 456
From: North Carolina
If when it does it you cut car off without clearing code and restart is it still messed up until clear code? Getting back to the battery even Lexus did not know what was going on in the beginning with the weird intermittent problems. I even took my car to an transmission only shop and they could not find any problems. I diagnosed the problem myself by trial and error measuring voltage and after replacing battery the problem never happened again. During that time I know someone that Lexus traded out because neither they nor corporate could figure it out. Now it is widely known. Difference here though is that mine never threw a code.
Thread Starter
Driver School Candidate
Joined: Oct 2025
Posts: 23
Likes: 3
If when it does it you cut car off without clearing code and restart is it still messed up until clear code? Getting back to the battery even Lexus did not know what was going on in the beginning with the weird intermittent problems. I even took my car to an transmission only shop and they could not find any problems. I diagnosed the problem myself by trial and error measuring voltage and after replacing battery the problem never happened again. During that time I know someone that Lexus traded out because neither they nor corporate could figure it out. Now it is widely known. Difference here though is that mine never threw a code.
I put it on a trickle charger all night and the issue remains.
Ive tried every forum posted option of repair.
Trickle charged on a battery thats less than 5 months old. Car has a new alternator.
New coolant sensor
New speed sensor
New S3 solenoid
New filter and pan gasket
New fluid with 3 drain and fills to the correct level between 115-130 degrees.
ECM repair from TechnicalDomain
Cleaned ECM connectors with Deoxit
Just looking for someone that’s had this exact issue before and found a fix.