LScowboyLS

sounds a lot like something I read in post #670

Shrugy

iTrader: (12)

Just sent mine to a man who does this service and had very good reviews.

I found him on eBay, and got my unit back today.

I plan to install it tomorrow and start it up and see how it runs, etc.

Will post again tomorrow letting everybody know how it went!

LScowboyLS

well if you didn't supply the capacitors from the links I provided, prepare to be disappointed, as their is currently no one on ebay rebuilding LS400 ECU's using the correct rare high temperature, long life, low-ESR, high ripple rejection premium Japanese capacitors!

It may work better than it did, if it was messed up bad enough, but without the correct capacitors, it will not perform like is should, and will quickly deteriorate from there - I thought I made this clear in post #1

You would not believe the horror stories we have uncovered in this very thread with all of the various ebay and other rebuilders (driftmotion, etc.)

mbonne

What leads you to believe that the metal PCB traces are being etched away.??

Anyone having replaced actually leaking capacitors have to do anything other than PCB cleanup.?

LScowboyLS

yes, some copper traces in some ECU's have been etched completely in half, and sometimes the damage is so bad that circuit board restoration, while perhaps possible in a lab, would cost more than the ECU is worth (since another ECU with no damage can be purchased on ebay, and then the defective series of Nichicon PF (M) and PR (M) capacitors can be replaced on the good condition circuit board of the replacement ECU, so that the replacement ECU doesn't suffer the same fate)

metalman

Ok, now, sorry just been busy since I got back home......I found out that the Toyota Sienna has coil connectors just the same. Plus up top and real CLEAN. So I spliced that in and resolved that issue. Also the clips for the Hi tension coil wire as well. Everything is nice and Snug. BUT......yea, there always a BUT.........now my power supple is on the brink. Once in awhile it will stop charging, all lights come on the dash. Already did new batter connectors, but I think its the part were the wire is crimped into the copper tab. (new alternator by nippondenso.) So I'm going to redo all those wires, and add an extra ground. I found this guy who also rebuilds these ECU's and uses the correct capacitors. I like the idea of getting another computer to do this, so I have a spare, and not miss my Lexus. I will give you a call.......when I get a chance to breath. despite the issues I'm having.........I love my Lexus, but in the future I'm looking forward to a newer one.....like to try the GS430, and if I don't like the ride, the LS430 is quite a car. My lesson learned is don't get freakin angry about it, because you can't think clearly. Amen.

BeLSNow111

Are there any known and recommended technicians in the Southern California area that maybe able to help me replace my capacitors on my ECU? I ordered the capacitors right now and they should be arriving in the next 2-3 days. I have soldered a couple of hobby projects but would prefer to go to someone experienced. Thank you in advance for your input!

metalman

O yea, bigger and better yet......found that transmission shift issue............on the kick down cable underneath the traction control panel where the throttle is, the Rubber Grommet came off it's perch and was catching the nub on the cable. I cut it off, see ya, put a dab of grease there. Now the car runs top, shifts great..........now I can move onto better things. btw, after the car wash in the cold yesterday....well....maybe not a good idea, now I have no electrical issues, but still will upgrade that due to the electronics this car has.

ckk0420

i have jest removed and checked the ecu in my 94 ls400 i found 1 maybe 2 capaciters that are leaking and one small spot one the board it dosent seem to bad im jest wondrin if thats enougth to cause severe driveabilty issues that are complety random

LScowboyLS

ANY capacitor leakage whatsoever is a HUGE problem for drivability! - it won't be long until the transmission will stop automatically shifting and you have to move the shifter manually!

Yamae

I recommend you to replace capacitors ASAP before they damage traces and the board. Sooner the better. You will also notice the improved driveability too.

dveneman

Hello,
New member here. I found a nice '98 LS400 and have plans to do the Yamae/Cowboy repair. Thank you for sharing all the info!!
My concern is the parts I received from the links you provided at Digi-Key. The various capacitors they shipped have "country of origin" as follows:
Japan, Malaysia, Indonesia and China. Will they be ok to use?
Thanks.

LScowboyLS

Yes, this is fine - these are the four big Japanese capacitor firms (Rubycon, Nippon Chemi-con, Nichicon and Panasonic) who make the best capacitors in the world, by a wide margin, and they have very tightly controlled factories in many countries - the main thing is that you purchased from DigiKey who is the largest authorized distributor for all 4 of these firms in the world. - So in this case, "made in Japan" is not as important as made by the best Japanese companies and not counterfeit.

It's like buying a Camry made in Kentucky, so tightly controlled in parts and labor that the Toyotas made in Kentucky have been as reliable as the Toyotas made in Japan, the main thing is that it is a Toyota, and not a Ford, Chrysler, Jaguar, Rover, or other problematic marque, etc.

The main thing I would focus on, is that unless you have a LOT of experience doing this kind of small soldering, that you practice extensively your soldering, desoldering, hole making, and rosin removal techniques on some old computer motherboards before trying this on your very expensive ECU!

KahnBB6

iTrader: (5)

I've been following this thread for a while now. Does the problem appear to affect ALL 1990's Toyota ECU's after enough time? I have a 1994 US 2JZGTE ECU that is just sitting in a box for now (I'm not ready to use it). Should I be concerned about getting its capacitors replaced as a matter of course?

Yamae

Not all of 1990's but many cars used Nichicon PF(M) and PR(M) series of electrolytic capacitors that contain the quaternaty ammonium salt.