Changing Factory ECU

[Skorov]

Over the last 2 months I've been dealing with issues related to my front o2 sensor. It's basically cutting in and out, voltage reads either 0V or 5V and switches between the two.

After much diagnostics, my mechanic and I have come to the conclusion that it is likely a faulty ECU. It has been reflashed many time, so it is entirely possible.

My question comes in a few parts.
Firstly, is it possible to switch the ECU with one from a wreck? I know there is a key code ID embedded in the ECU (hardware or software?) which communicates with the "Certification ECU". I have keyless entry/start. This code ID needs to be registered in the Certification ECU for them to talk.
If possible, what is the process for performing the switch?

I have also been informed of a concept that was called "Neutralizing the ECU" or "Initializing the ECU". Apparently, this *might* be required before it is installed in a new vehicle. Can this be done if the ECU has already left the wreck? If so, how?

I've read and been told so much conflicting information and was hoping that someone with good knowledge could shine some light into how this all works. I would prefer to keep speculation out of this thread and stick to proven facts.

If any Toyota/Scion/Subaru ECU specialist could impart their wisdom, I would be forever grateful!

Many thanks!

[steve99]

Originally Posted by Skorov

Over the last 2 months I've been dealing with issues related to my front o2 sensor. It's basically cutting in and out, voltage reads either 0V or 5V and switches between the two.

After much diagnostics, my mechanic and I have come to the conclusion that it is likely a faulty ECU. It has been reflashed many time, so it is entirely possible.

My question comes in a few parts.
Firstly, is it possible to switch the ECU with one from a wreck? I know there is a key code ID embedded in the ECU (hardware or software?) which communicates with the "Certification ECU". I have keyless entry/start. This code ID needs to be registered in the Certification ECU for them to talk.
If possible, what is the process for performing the switch?

I have also been informed of a concept that was called "Neutralizing the ECU" or "Initializing the ECU". Apparently, this *might* be required before it is installed in a new vehicle. Can this be done if the ECU has already left the wreck? If so, how?

I've read and been told so much conflicting information and was hoping that someone with good knowledge could shine some light into how this all works. I would prefer to keep speculation out of this thread and stick to proven facts.

If any Toyota/Scion/Subaru ECU specialist could impart their wisdom, I would be forever grateful!

Many thanks!

I don't think flashing your ecu has caused problems one guy at least has done more than 1500 flashes and i know a few guys who would be over 300.

AFAIK if you buy a brand new ecu that has not been used before a dealer can code it in to your

A used ecu i believe it cannot be done due inbuilt security in ecu but i am not 100% on this amybe ask dealer if they can code in used ECU. . But you can get the complete security set from a wrecked car, you need ECU, Immobilizer module, Dash cluster, and ignition switch(if keyed)keys/fob(for push button start), and swap entire set to your car, no coding required.

[Wayno]

If it alternates between only 2 values, are you absolutely sure you don't have the plugs reversed?
The rear narrowband will give you 2 values - too rich and too lean.

If it's an intermittent signal, that indicates a connection problem, likely at a pin. Replacing an ecu won't fix a loose pin/joint. It would suck if you went to all the time and expense of sourcing another ecu, having to deal with a dealer to initialize it, etc and it turns out the current ecu is fine.

ECU's are good for 10,000 flashes or so. Mine has well over 100, maybe 200. Unless you have a tuning/development car you it's extremely unlikely that you will kill the ecu by over flashing.

[ztan]

1. Have you checked the signal both at the sensor and the ECU? If you are reading the Front O2 off RAM, which RAM address are you logging and which software?

2. The Front Wideband is calibrated in current rather than voltage - I am not exactly aware of what the control circuitry is, but if a PWM current then 0 and 5V may be appropriate.

3. ECU immobilizer info from the manual:

1. Description of the engine immobilizer system
(1) The engine immobilizer system records the key ID in the main body ECM (multiplex network body computer). If the key ID and the code recorded in the main body ECM do not match, the engine immobilizer system prohibits the engine from starting.


2. Functions of the main parts
Components
Summary
Main body ECM (Network gateway computer)
This checks if the key ID received from the transponder key amplifier matches the registered key ID. Concurrently, it communicates with the combination meter ASSY*1 or the transponder ECM*2 and checks that the key ID (meter ID) recorded in the combination meter ASSY*1 or transponder ECM*2 matches the ID (meter ID) recorded in the main body ECM. Based on the request from the engine control computer, it encrypts each collation result and registered ID (engine ID), and sends them to the engine control computer.
Combination meter ASSY*1
Based on the request from the main body ECM (network gateway computer), it encrypts the registered ID, and sends it to the main body ECM (network gateway computer).
Transponder key ECM ASSY*2
Based on the request from the main body ECM (network gateway computer), it encrypts the registered ID, and sends it to the main body ECM (network gateway computer).
Transponder key amplifier
This receives the key ID from the antenna coil, and outputs the key ID, which was amplified by the amplifier, to the main body ECM (network gateway computer).
Engine control computer
When the engine starts, this communicates with the main body ECM (network gateway computer), and receives the key ID, the meter ID collation result, and the encrypted ID (engine ID) of the main body ECM (network gateway computer). If any of them do not match, it stops (prohibits) the engine from starting.
Unlock warning switch ASSY
This detects a key inserted in the key cylinder and outputs the result to the main body ECM (network gateway computer).
*1: With a transponder ECM
*2: Without a transponder ECM


3. System functions
(1) When the main body ECM (network gateway computer) detects that the unlock warning switch ASSY is ON, it powers the transponder key amplifier and generates a magnetic field around the antenna coil. The transponder chip inside the key grip outputs a key ID signal by the electromotive force generated by the magnetic field. The transponder key amplifier receives the key ID code signal, amplifies it by an amplifier, and sends it to the main body ECM (network gateway computer).
The main body ECM (network gateway computer) checks if the key ID received from the transponder key amplifier matches the registered key ID. Concurrently, the main body ECM (network gateway computer) communicates with the combination meter ASSY*1 or the transponder ECM*2 and checks that the ID (meter ID) recorded in the combination meter ASSY*1 or transponder ECM*2 matches the ID (meter ID) recorded in the main body ECM (network gateway computer).
When starting the engine, the engine control computer communicates with the main body ECM (network gateway computer), and checks the collation result between the key and the combination meter ASSY*1 or the transponder ECM*2. Also, it checks if the ID (engine ID) recorded in the main body ECM (network gateway computer) matches, and if any does not match, it stops the engine from starting.
*1: With a transponder ECM
*2: Without a transponder ECM

4. Recoding ECU is, in general, a dealer only function. If you find a locksmith who can sync ECU, immobilizer, dash cluster, transponder and keys in Australia, please let me know...

5. I bricked my ECU and the dealer said he could try to recode a second hand ECU but said it might not work unless I had the keys it had been coded with originally. Wreckers may charge a fair bit for matching ECU, dash cluster, immobilizer, and keys and there is no guarantee that they will work at this stage. I ended up going with new ECU from dealer.

[Skorov]

Hi all,

Thanks a lot for the awesome info.

I took my car to two Toyotas. The first was mostly useless, the second managed to do it!

Here is what I learned:
1. The ECU needs to be "neutralised" as the technician called it. This should be done on the original vehicle before the ECU is taken off.
2. Alternatively, if you have the ECU the Certification ECU, immobiliser and the key fob from the wreck, you could plug all these into your car and neutralise the ECU.
3. Your original devices can now be reinstalled along with the new ECU. From here the process is basic and any dealership* should be able to do it.
@ztan: I had this done at Phil Gilbert Toyota in Croyden NSW. I imagine it's possible for them to sync the rest too. If you're interested, PM me and I can give you a contact there who was extremely helpful.

This *seems* to have fixed the issue! The voltage now reads ~2.7V at idle. Don't want to get my hopes up yet. Still need to drive it to the tuner for the reflash and dyno tests. But we have progress!!


*NOTE: By any dealership, I mean any competent dealership.

[ztan]

Originally Posted by Skorov

1. The ECU needs to be "neutralised" as the technician called it. This should be done on the original vehicle before the ECU is taken off.
2. Alternatively, if you have the ECU the Certification ECU, immobiliser and the key fob from the wreck, you could plug all these into your car and neutralise the ECU.

Trouble is getting a wrecker (usually even less helpful than a dealer) to know how to deal with the ECU before sending it out, getting all the matching parts makes the wreckers keen to charge you even more with no certainty that what they send you will actually work. I decided to use the dealer - it was certainly less of a hassle than trying to deal sensibly with wreckers who don't have any real info on these systems.

[steve99]

Originally Posted by ztan

Trouble is getting a wrecker (usually even less helpful than a dealer) to know how to deal with the ECU before sending it out, getting all the matching parts makes the wreckers keen to charge you even more with no certainty that what they send you will actually work. I decided to use the dealer - it was certainly less of a hassle than trying to deal sensibly with wreckers who don't have any real info on these systems.

The guys below quoted me about $550 for a full security set including dash ecu imobiliser and key fob, which i thought was reasnoble they do a lot of subaru stuff and seem to be across subaru security to some degree.

http://www.sunspares.com.au/

[ztan]

Originally Posted by steve99

The guys below quoted me about $550 for a full security set including dash ecu imobiliser and key fob, which i thought was reasnoble they do a lot of subaru stuff and seem to be across subaru security to some degree.

http://www.sunspares.com.au/

That is quite reasonable if it all works, though odometer would presumably be off.