ECM Procedure Help Request - 2000 LX470 (2 Viewers)

[cumminsBase]

Hello,
I'm trying to marry a used ECM to my 2000 LX470.

I tried with Techstream, and although I connected to all modules, I don't see a procedure to "marry" the new (used) ECM into the vehicle.
I then tried the procedure I saw in this video link (linky link), yet after 30 minutes nothing changed. The vehicle still did not want to fire up (engine cranks, nothing fires up).

Any ideas on how to go about it?

I do have my original ECM, which has two master keys registered (and I have both of these keys in my possession).

Why change the ECM?
About two weeks ago I was idling in a parking lot, and in about 15 minutes the engine started running rough and shut off.
I fired her back up and she fired perfectly... and within seconds same stutter and off.
I rode her home, and basic DTC codes indicated the MAF.

So I pulled out the service manuals, and followed the procedures.
Pin 5 was not receiving the voltage indicated.
Next step was checking if the ECM was outputting the voltage on PIN xyz (forgot which one, yet I can look it up).
Well behind the glove compartment I probed the ECM pin xyz, and it did NOT have voltage.
A next test states that if yet another pin is outputting between 2.5 and 5 volts (I think), then: Replace ECM.


Any thoughts on what I can try next?
Thank you!

====
EDIT: If I re-install my original ECM, the vehicle fires right up with the rough idling.

 

[Trunk Monkey]

@Mauser, time for your expertise.

 

[Mauser]

Hello,
I'm trying to marry a used ECM to my 2000 LX470.

I tried with Techstream, and although I connected to all modules, I don't see a procedure to "marry" the new (used) ECM into the vehicle.
I then tried the procedure I saw in this video link (linky link), yet after 30 minutes nothing changed. The vehicle still did not want to fire up (engine cranks, nothing fires up).

Any ideas on how to go about it?

I do have my original ECM, which has two master keys registered (and I have both of these keys in my possession).

Why change the ECM?
About two weeks ago I was idling in a parking lot, and in about 15 minutes the engine started running rough and shut off.
I fired her back up and she fired perfectly... and within seconds same stutter and off.
I rode her home, and basic DTC codes indicated the MAF.

So I pulled out the service manuals, and followed the procedures.
Pin 5 was not receiving the voltage indicated.
Next step was checking if the ECM was outputting the voltage on PIN xyz (forgot which one, yet I can look it up).
Well behind the glove compartment I probed the ECM pin xyz, and it did NOT have voltage.
A next test states that if yet another pin is outputting between 2.5 and 5 volts (I think), then: Replace ECM.


Any thoughts on what I can try next?
Thank you!

====
EDIT: If I re-install my original ECM, the vehicle fires right up with the rough idling.

I would just swap the IC900 chip from the old one to the new one. Its just a small surface mounted eeprom.

 

[cumminsBase]

I would just swap the IC900 chip from the old one to the new one. Its just a small surface mounted eeprom.

I can do that!
Is it labeled IC900 on top?
Or is it easy to ID?

AWESOME!!!

THANK YOU!!!

 

[Mauser]

I can do that!
Is it labeled IC900 on top?
Or is it easy to ID?

AWESOME!!!

THANK YOU!!!

There is an IC900 printed on the board.

 

[Malleus]

That's a FAQ candidate

 

[cumminsBase]

That's a FAQ candidate

I'll snap photos!!

Out of personal curiosity: what's the procedure to marry a new ECM?
I reckon Techstream can't do it?
Is there another special service tool?
Or does it get more in-depth hacky with the board itself?

Thank you!

 

[Mauser]

I'll snap photos!!

Out of personal curiosity: what's the procedure to marry a new ECM?
I reckon Techstream can't do it?
Is there another special service tool?
Or does it get more in-depth hacky with the board itself?

Thank you!

You have to pull the eeprom and program it with either key info, or the auto registration code.

 

[cumminsBase]

Ok, so I left the hot-air gun station at work...
Tomorrow I'll take both boards (ECMs) into the office and do it there.

Yet, inspecting the old board at home...
where the heck is the IC900?

I can identify almost all other ICs, except the 900.

EDIT!
As I type this, I look down and see IC900.
Small 8-legged bugger.

I attach two photos to contribute.

 

[cumminsBase]

One more close up of IC900

 

[Mauser]

@cumminsBase Sounds like you have it covered. Let me know if you need anything. If you need a chip with the auto registration code I can help with that too.

 

[cumminsBase]

Some photos... and it worked!

I'll post the photos, and then write another reply in 10 minutes...

 

[cumminsBase]

Alright!
So first the good news:
The IC900 chip replacement work PERFECTLY!
Thank you @Mauser!!

Vehicle started up as if nothing happened.
I'm amazed that the problem was actually the ECM.
I haven't confirmed I'm getting the correct voltages in the MAF, yet I'll do it later.

Some bad news: battery seems to have died, as I left it a couple of days connected with the ECM unplugged. Apparently the other computers didn't go to sleep and drained the battery.

Good news: That's a simple fix, and I'll get another battery today.

Bad news: the engine has a clack-clack that it did not have before, nowhere nor anything like it.
Previous to this ordeal the engine purred like only those Toyota V8s do.
Perfect idle and perfect rev-up/down.

Yet now it has a clack clack as if a freaking connecting rod was thrown.
Oil level is almost full, and last oil change was about 2,000 miles ago this year.
Oil looks good (not dark).

When I rode the LandCruiser home with the fault (2 weeks ago-ish), she did stutter and pull when the MAF would fail and the computer would try to connect.
I think with those stutters I f'ed up the engine.

 

[cumminsBase]

@cumminsBase Sounds like you have it covered. Let me know if you need anything. If you need a chip with the auto registration code I can help with that too.

Although the IC900 desolder/resolder worked, I would love to know what this chip with auto registration code entails.

That's a part of working with cars that I've never gotten into (eeprom, etc).
Is that like: removing the chip and a "univeral code" that will re-program it?

I'm just really curious as to a 10,000 feet view of what this is like.

THANK YOU FOR YOUR HELP Mauser!

 

[cumminsBase]

Hey, throwing ideas out there:
Did these era V8 engines all have the same firing order?

If there were different firing orders... could I have ordered/received the wrong ECM?

It's just so odd that the engine has this heavy metal clacking sound.

 

[cumminsBase]

Well, this has been a mega humbling experience for me... yet:
It was the MAF.

Why I didn't check it before?
God knows.

I dived straight into the Service Manual, and started a train of assumptions.
I'm going to re-read the Service Manual, to see where I mis-undertood to jump into the voltage checks in the MAF plug.

I doubt I needed a computer (although it was fun!).
New MAF from AutoZone fixed the issue straight up.

 

[Mauser]

Well, this has been a mega humbling experience for me... yet:
It was the MAF.

Why I didn't check it before?
God knows.

I dived straight into the Service Manual, and started a train of assumptions.
I'm going to re-read the Service Manual, to see where I mis-undertood to jump into the voltage checks in the MAF plug.

I doubt I needed a computer (although it was fun!).
New MAF from AutoZone fixed the issue straight up.

Message me an address. I will send you an eeprom with the auto-reg info written to it. You can solder it to your old ecu and have a spare or whatever.

Or if you want to try programming the eeprom this is the info to write to it:

 

[87warrior]

Well, this has been a mega humbling experience for me... yet:
It was the MAF.

Why I didn't check it before?
God knows.

I dived straight into the Service Manual, and started a train of assumptions.
I'm going to re-read the Service Manual, to see where I mis-undertood to jump into the voltage checks in the MAF plug.

I doubt I needed a computer (although it was fun!).
New MAF from AutoZone fixed the issue straight up.

You are not alone.

The MAF is definitely a critical sensor for the 100. If the sensor or circuity for the sensor is not up to snuff it can cause havoc! I chased a MAF circuit issue that was leading to random stalling for quite awhile.