Club Lexus is fantastic and has so far saved me over $1000!! Immediately after purchasing, I went through my car and replaced just about everything that people said were problems with the SC's. (broken or not). A couple of weeks ago, my car started running terribly (I would call it barely). To the point were I had to have it towed. It would run for a couple of minutes, then start cutting out terribly and died any stop. Threw errors 31 & 41. I took it to a mechanic to fix, but he said before he could even diagnose it, that "he" had to fix a leak in the Heater Valve. $500 repair cost. After research, I found the fixes for it, fixed myself for $30. Once that was fixed, the car appeared to run ok-ish, but I didn't trust it as I drive 120 miles per day. In researching the error codes, the AllData troubleshooting guides said it's either the sensors or the ECM. So I started researching ECM and came across this thread. For the cost of the CAP and Shipping ($16), I said let's give it a try. So I just completed the replace last night, plugged in the ECM, car started right up, drove it about 10 miles. I "think" it's running better, and I "think" it's shifting much better. Time will tell..

But, HUGE thanks for LScowboyLS & Yamae (and all the other people who provided comments) for the post.

 

CowboyLS would you give me a call. Wheel man recommended me to reach out to you about my 2000 LS400. 202-817-0225.

 

May contact Tanin Auto as well:
https://www.clublexus.com/forums/ls-...l#post10437108

If you prefer cowboy his FB page is here:
https://www.facebook.com/LScowboyLS/

I would suggest removing your personal contact info from your post.

 

thelexpert@gmail.com

 

My ECU question does not directly pertain to caps, but since this is the definitive ECU thread on CL, I'll ask it here:

The ECU in my 92 SC400 seems to have failed (no start, no Check Engine light). I carefully opened it up and the caps looked perfect (I know they can still be bad).
So I sent it to our buddies at Tanin for a fix (tickets 49842/51070). After taking a look, Tanin said they can't fix it.
They would not say specifically why they can't fix it, but they offered to sell me a replacement for $399.
I called back a few more times, asking them to ask the tech specifically why it's unrepairable, and they were very polite each time, took down my question and promised to call back, and each time they called back with the answer of "it can't be repaired" and nothing else.

So I am assuming it's worse than just the caps, and that one or more of the large chips/ICs on the circuit board has failed.
I could be wrong, but in all my research on the web, and after calling a few more ECU repair shops, it doesn't seem that any of them tackle anything beyond replacing the caps.
OK, fine, so my ECU is unrepairable, has no salvage value and I gotta buy a replacement.
I can handle that - just one last question:

Is there a chance some electronic failure elsewhere in my car caused my ECU to fail?
Some of the ECU repair shops state on their websites - "ECUs rarely fail on their own, so before replacing the ECU, ensure that nothing else in the car has triggered the failure". Great advice, but where do ya start?
Has anyone heard of this happening in our cars?
I'd hate to spend hundreds of dollars on a replacement and have it pop the minute I power it up!

 

Being in socal,and with an early model,pick your part has a billion of these cars here.So getting one shouldnt be hard or expensive.I havent followed the sc400,but early ls400,dime a dozen here.

 

It's not that the ECU is,"not repairable", but for $149 it's not worth it to us to reverse engineer every single problem with the ECU's and try to pinpoint a DOA ECU that has no visible signs of trauma or damage. There is a trade-off between efficiency, payroll, running a business, priorities, repair queue load, etc, etc, etc.

In cases like these we simply offer a tested, working ECU to get it out the door and make the customer happy. There is only so much time in a day and we can't spend hours upon hours with an ECU otherwise we would be losing money.

We have a bin of 100+ ECU's that I'm sure we will work on when we hire 1-2 techs that simply reverse engineer and rebuild ECU's all day, but it's just not a priority right now.

Without explaining that whole story to every customer, we say it's not repairable, the repair price doesn't cover issue XYZ on this ECU, or we can't repair it. Maybe someone can, or someone has figured out every single issue with these ECU's, or maybe those people just give you a different ECU circuit board and say, "ok it's fixed".

As far as your last question we have only had one customer ever fry an ECU after replacing it and that was caused to many major grounding issues and water intrusion/flooding. So with 99% certainty a replacement ECU will solve your problem and you likely won't have to ever worry about it again.

Hope this helps

 

I only can comment on your above statement and the question.

As far as I analyse variety of failed ECUs just for my curiosity, the failed electrolytic capacitor is just one of them. Of course it used to be many simply because capacitors containing quaternary ammonium salt inside were widely used in many 90's cars. There were failed semiconductors and other components too in addition to soldering cracks. Most of semiconductor failures are caused by the short-circuited motors, solenoids or cables and without finding the root cause, there happens the ECU failure again. I hope your car does not have any failures that kill the ECU every time you change it.

 

Well, all three of you were right - spuds was right in that a replacement wasn't that expensive.
I found an ECU on eBay for ~$150.
It arrived today, and as Tanin predicted, it solved my problem (namely, that it would not start!).
After sitting unused since November, the car started instantly once the new ECU went in.
And Yamae's wish that there were no failures anywhere else to ruin my new ECU came true - whatever went wrong with my old ECU wasn't caused by a short elsewhere in the car.
And it wasn't caused by the usual caps, otherwise Tanin could have/would have fixed it.
I spent a lot of time since November checking my fuel and ignition systems when I should have gotten busy getting another ECU!
Lesson learned - these ECUs can fail anytime, for no reason at all, and should be suspect #1 in most, if not all, "no-start" and "poorly-running" situations.

 

Thats really good news Perry.Congrats on the fix.

 

Great news! Highly recommend getting that ECU rebuilt now before you run into the same issues down the road. Every one of them will have some form of cap leakage.

 

Except the one that I sent to you, right?

 

Not sure what the techs found specifically with yours. There was no major leakage all over the board. There could have been some starting under the caps or like you mentioned going bad internally, prior to leaking out.

 

I'm not sure, either, because I never got a straight answer from your staff except "it can't be fixed, but we'll sell you a replacement for $399".
But it couldn't be the caps - that's what you guys do, right?
You replace the caps, and the ECU works again. You've done it a hundred times.
But since your staff said it can't be fixed, it must have been something besides the caps.
So, as I said, the caps were fine, and, unlike what you said, not all of them have some form of cap leakage.

 

No, not entirely true. The caps can be bad and even leaking all over the board and an ECU will still "work" and a car will run without any visible issues, or have very slight noticeable issues such as a hiccuping idle.

If you open up your new ECU you will likely see some signs of cap failure if they haven't been serviced before.