ECM Rebuild - Sources?
Thread Starter
10th Gear
Joined: Sep 2024
Posts: 11
Likes: 6
ECM Rebuild - Sources?
I'm thinking about having my ECM rebuilt, more of a precaution than anything else. I've read that SIA Electronics is a place a lot of people have used. Are there any other reputable shops for this?
Thanks!
Thanks!
Instructor
Joined: Jan 2018
Posts: 980
Likes: 303
From: WA
Check out 400Fanboy's recent post in the 1st and 2nd gen forum about his experience with SIA. A tale of woe.
https://www.clublexus.com/forums/ls-...ed-my-car.html
https://www.clublexus.com/forums/ls-...ed-my-car.html
Last edited by TominPT; Oct 8, 2024 at 11:19 AM.
Instructor
Joined: Jul 2010
Posts: 778
Likes: 112
From: MI
I'm not sure that I would do it on a proactive basis. They do not rebuild the entire unit, only the parts that affect your problem and other common problems. If it's not broke, don't fix it. That said, I used and recommend Relentless in suburban Dallas. If you contact the owner, he may have an opinion that he will be happy to share.
Last edited by LS430Lexus; Oct 9, 2024 at 12:16 PM.
Instructor
Joined: Nov 2007
Posts: 1,117
Likes: 287
From: CA
Captain Obvious here -
This is a must read along with the 400Fanboy thread: https://www.clublexus.com/forums/ls-...capacitor.html
This is not to say it doesn't happen; it wouldn't hurt to be proactive and take a look for the start of leakage. But this too has associated risks - ESD discharge, pin connector damage, etc.
I don't believe capacitor issues plague the '98 - up model years like the 1990-1997's. If there ever was a, "don't fix it if it ain't broke", this is one of them.
Picking the right vendor to do the work is also important.
This is a must read along with the 400Fanboy thread: https://www.clublexus.com/forums/ls-...capacitor.html
This is not to say it doesn't happen; it wouldn't hurt to be proactive and take a look for the start of leakage. But this too has associated risks - ESD discharge, pin connector damage, etc.
I don't believe capacitor issues plague the '98 - up model years like the 1990-1997's. If there ever was a, "don't fix it if it ain't broke", this is one of them.
Picking the right vendor to do the work is also important.
Racer
Joined: Jan 2017
Posts: 1,977
Likes: 822
From: TX
I'm not sure that i would do it on a proactive basis. They do not rebuild the entire unit, only the parts that affect your problem and other common problems. If it's not broke, don't fix it. That said, I used and recommend Relentless in suburban Dallas. If you contact the owner, he may have an opinion that he will be happy to share.
https://www.ebay.com/itm/116157858115 this person also does the service.
But yeah, if it ain't broke, don't fix it in this scenario. I like to be proactive in the maintenance approach to my car but with this, not so much.
Instructor
Joined: Jul 2010
Posts: 778
Likes: 112
From: MI
It may depend on his mood. He turned mine around in 24 hours. Overnighted on a Monday on the way to the airport, I received it back on Friday when I returned. I was out of town for the week so no downtime.
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Someone here recommended this place
https://stores.digitalautotech.com/l...epair-service/
I want to send my ECU in too because everytime time I reset the ECU the car feels peppy. Then a few days later it feels lazy. I contacted the eBay guy and he was very responsive and he said:
Harsh downshift is the most common issue in that computer. It’s hard to say if a rebuild will fix your problem or not, but it can correct other issues. When you’re doing a reset it has to go through and learn adaptive. It sounds like it’s just learning something each time, it’s not a bad idea to get the computer done because it will fail in the downshift area
The eBay guy has the best price out of SIA, relentless and DAT.
I might bite the bullet and take my ECU to DAT since they are only 5 hours away from me.
https://stores.digitalautotech.com/l...epair-service/
I want to send my ECU in too because everytime time I reset the ECU the car feels peppy. Then a few days later it feels lazy. I contacted the eBay guy and he was very responsive and he said:
Harsh downshift is the most common issue in that computer. It’s hard to say if a rebuild will fix your problem or not, but it can correct other issues. When you’re doing a reset it has to go through and learn adaptive. It sounds like it’s just learning something each time, it’s not a bad idea to get the computer done because it will fail in the downshift area
The eBay guy has the best price out of SIA, relentless and DAT.
I might bite the bullet and take my ECU to DAT since they are only 5 hours away from me.
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Racer
Joined: Jan 2004
Posts: 1,985
Likes: 488
From: North Carolina
Someone here recommended this place
https://stores.digitalautotech.com/l...epair-service/
I want to send my ECU in too because everytime time I reset the ECU the car feels peppy. Then a few days later it feels lazy. I contacted the eBay guy and he was very responsive and he said:
Harsh downshift is the most common issue in that computer. It’s hard to say if a rebuild will fix your problem or not, but it can correct other issues. When you’re doing a reset it has to go through and learn adaptive. It sounds like it’s just learning something each time, it’s not a bad idea to get the computer done because it will fail in the downshift area
The eBay guy has the best price out of SIA, relentless and DAT.
I might bite the bullet and take my ECU to DAT since they are only 5 hours away from me.
https://stores.digitalautotech.com/l...epair-service/
I want to send my ECU in too because everytime time I reset the ECU the car feels peppy. Then a few days later it feels lazy. I contacted the eBay guy and he was very responsive and he said:
Harsh downshift is the most common issue in that computer. It’s hard to say if a rebuild will fix your problem or not, but it can correct other issues. When you’re doing a reset it has to go through and learn adaptive. It sounds like it’s just learning something each time, it’s not a bad idea to get the computer done because it will fail in the downshift area
The eBay guy has the best price out of SIA, relentless and DAT.
I might bite the bullet and take my ECU to DAT since they are only 5 hours away from me.
Pit Crew
Joined: Aug 2021
Posts: 111
Likes: 25
From: TX
Considering rebuild
I’m considering a ECM rebuild, but for a very different reason. I’ve tried every possible route to fix the check vsc issue - including replacing the solenoid. No matter what, once I hit the parameters for the error (50+ mph and 2 occurrences from key off to key on) it always comes back.
in the history of the vehicle, I can see it started occurring after the factory recall of the transmission caused the owner to replace. So, I think it MUST be the computer. I hate to do it being proactive and risk messing up other stuff but in my case it seems worth it?
in the history of the vehicle, I can see it started occurring after the factory recall of the transmission caused the owner to replace. So, I think it MUST be the computer. I hate to do it being proactive and risk messing up other stuff but in my case it seems worth it?
Driver
Joined: Aug 2016
Posts: 59
Likes: 18
From: Sunny Bay Area, CA
Thanks to this member RomanNOVA for the eBay posting ECU rebuild, I have 2005 LS430 with only 137k+ miles and a few weeks back the tranny start doing the 3-2 harsh and 2-1 shocking violent down shifting, this person fixed or rebuilt the ECU within 1 week of turnaround time, the car is happily back on the road again. The transmission shift pattern now is better than the day I owned this car since 2016, the downshifting pattern almost inexistence from any speed to 0 mph! No issue starting the vehicle after the rebuilt, 2 thumbs up for this seller.
Here is the listing on eBay. Lexus LS430 ECU computer Rebuild service 04-06 Harsh transmission shift | eBay
Here is the listing on eBay. Lexus LS430 ECU computer Rebuild service 04-06 Harsh transmission shift | eBay
Last edited by nedear1688; Oct 24, 2024 at 10:10 AM.
Racer
Joined: Mar 2018
Posts: 1,304
Likes: 402
From: ESSEX, UK
In the LS430 ECUs the problem is not the capacitors, it's the lead-free solder that was used.
That 1st generation lead-free solder gets brittle with age and cracks causing weird and often intermittent issues.
Many of the ECU repair companies reflow the solder joints with better quality solder and most of the time that fixes the problem.
The good places will have an ECU test jig and will test it fully after reflowing to see if there are any other issues.
That 1st generation lead-free solder gets brittle with age and cracks causing weird and often intermittent issues.
Many of the ECU repair companies reflow the solder joints with better quality solder and most of the time that fixes the problem.
The good places will have an ECU test jig and will test it fully after reflowing to see if there are any other issues.
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