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Discussion Starter #1 (Edited)
Hello!
I'm new to this forum and I figured out how to wire the stock auto ecu without ANY error codes AND with smooth power delivery!
I want to share this easy and free mod with you guys since manual ECUs are getting more rare and expensive and are only available on the US market.

The first thing you need to do is to wire up the park/neutral position switch and AT indicator switch connector correctly.
It was plugged into the AT and looks like this:

(picture from Curran)
135141


Connecting the two black wires together allows your engine to start.

Connecting the two red (red/black and red/blue) wires to your reverse light switch lets your reverse lights light up when put in reverse.

This is the way people did it until now. the problem is, the ECU thinks the AT is in no gear while driving, it only knows when you are going in reverse.
This is also the reason for the bad throttle response and no smooth power delivery.

Connect the grey wire to the red/blue wire to tell the ECU that the AT is in 2nd gear.

We have a few problems now:
As soon as you put your car in reverse, you will get an error code because the ecu thinks it is in reverse AND 2nd.
This is solved by simply cutting the red/black wire (connector D, pin 5) on the ecu connector.

135142

Now the ECU will never know when you put your car in reverse. fooled.

Next thing you want to do is, to put the car in 1st/L since this is the only gear the ECU doesnt try to shift. This is done by connecting the two wires on one of the connector in the drivers compartment where your AT shift lever was.
Connect the Yellow/Green wire to the Green/Yellow wire.

135143


When you are already here, you can also activate the ECT/PWR mode. I dont know if this does something, but it cant be bad.
Connect brown and blue/white:
135144


now your cluster should show L and ECT:
135145


Now you will have two error codes left, AT input RPM and output RPM. This is where it gets tricky, but my genius found the solution:
Connect the two Sensor+ wires from the rpm sensors to the CAM sensor! Because its a VR-type sensor, we can share the signal.
So go back to the ECU and connect O/D Clutch Speed Sensor (D, 21, red) and vehicle speed sensor (D, 23, blue/yellow) to the CAM sensor input (E, 29, green).
135146

FOOLED!

You are done! assuming you already dealt with the transmission solenoids and temperature sensor.
the easyest way is to open the AT and unscrew the solenoids and the temperature sensor. now you can pull the whole harness out of the AT and plug it into the car.
put it in a bag or something and strap it to the car. Dont forget that all the solenoids with only one wire need to be grounded! screw them together in pairs and connect them with ring cable lugs to the car. i used the brake line bracket near the tranmission.

If you want a more elegant way or you still need the AT, you also can solder some resistors in place of the solenoids. Note that the 10 Ohm resistors have to be at least 10Watts or they will burn. This is the connector from the CAR, looking onto it as you were the other one wanting to plug into it :)
135147

You also could do this at the ECU, but i wont overcomplicate things now.

The only thing missing now, is working cruise control. I already figured out a way to do it, but it would cost arount 100$ to do it.

I hope i could help many guys with my solution and save tons of caashh! :)))
 

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MSM 2005 Lexus IS300 5AT
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Nice writeup! Do you have details on the trans solenoids/temp sensor? The popular thread takes care of CEL by switching to manual ECU and wiring the speed sensor to suit (Auto to Manual Swap, Wiring, Ecu, CC, NSS, CLSW, Trac...). Is there another thread that covers this?

I remember reading the solenoids get hot while driving and they need airflow to stay cool, so they would be mounted somewhere under the car. Not sure how accurate that is, and I can't find that thread anymore :/. Is that true? Is the whole package bulky and ugly to look at beneath the car? Perhaps also make the car less capable in inclement conditions (snow, salty roads) because of exposed solenoids mounted under the car?

It's a lot of questions, but I've never seen a picture of such a setup before, and am completely relying on visualization lol. It's a new concept to me, I haven't heard of other makes/models that need to retain the solenoids in a manual swap 馃

P.S.: Good taste in profile pic btw, head-on shots are one of the best angles of these cars lol
 

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Discussion Starter #3
Yeah its 7 solenoids and every single one is going to give you an error code and pop the CEL , just like the transmission temp sensor. I put the solenoids in a thick nylon bag and strapped them to the brake line bracket right beside the bellhousing. it is pretty waterproof and its not visible because its under the plastic cover. they shouldnt get hot if you wire it like me, since the car is in "L" and it doesnt try to shift. the beauty of my solution is, you dont need to mess around with any speed sensors. the signal of the cam sensor is just fine to keep the ecu thinking everything is all right.
if i did it again, i would wire the resistors to the ecu harness because its invisible and not exposed to the elements. maybe one day i will do it but for now i am just happy i got rid of all the error codes. also it would be interesting to see if there are any power gains from replacing the AT temperature sensor with a resistor. maybe the ecu cuts some power because it thinks the transmission is still cold(sensor hanging under the car). if i decide to rewire it, i could check it since i have free dyno access :)
 

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Do the reverse lights on the car still work like normal? Would a backup camera still trigger off the reverse wire that is in the driver kick panel? I'm certainly interested in this as I'm currently NA-T automatic but would like to eventually do a manual swap and have no desire to change the cluster or ecu, if not required.
 

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Discussion Starter #5
reverse lights work like normal. you are cutting the wire right at the ecu plug. only the ecu doesnt get to know you are in reverse!
 

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2004 IS300
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reverse lights work like normal. you are cutting the wire right at the ecu plug. only the ecu doesnt get to know you are in reverse!
Hello!
I'm new to this forum and I figured out how to wire the stock auto ecu without ANY error codes AND with smooth power delivery!
I want to share this easy and free mod with you guys since manual ECUs are getting more rare and expensive and are only available on the US market.

The first thing you need to do is to wire up the park/neutral position switch and AT indicator switch connector correctly.
It was plugged into the AT and looks like this:

(picture from Curran)
View attachment 135141

Connecting the two black wires together allows your engine to start.

Connecting the two red (red/black and red/blue) wires to your reverse light switch lets your reverse lights light up when put in reverse.

This is the way people did it until now. the problem is, the ECU thinks the AT is in no gear while driving, it only knows when you are going in reverse.
This is also the reason for the bad throttle response and no smooth power delivery.

Connect the grey wire to the red/blue wire to tell the ECU that the AT is in 2nd gear.

We have a few problems now:
As soon as you put your car in reverse, you will get an error code because the ecu thinks it is in reverse AND 2nd.
This is solved by simply cutting the red/black wire (connector D, pin 5) on the ecu connector.

View attachment 135142
Now the ECU will never know when you put your car in reverse. fooled.

Next thing you want to do is, to put the car in 1st/L since this is the only gear the ECU doesnt try to shift. This is done by connecting the two wires on one of the connector in the drivers compartment where your AT shift lever was.
Connect the Yellow/Green wire to the Green/Yellow wire.

View attachment 135143

When you are already here, you can also activate the ECT/PWR mode. I dont know if this does something, but it cant be bad.
Connect brown and blue/white:
View attachment 135144

now your cluster should show L and ECT:
View attachment 135145

Now you will have two error codes left, AT input RPM and output RPM. This is where it gets tricky, but my genius found the solution:
Connect the two Sensor+ wires from the rpm sensors to the CAM sensor! Because its a VR-type sensor, we can share the signal.
So go back to the ECU and connect O/D Clutch Speed Sensor (D, 21, red) and vehicle speed sensor (D, 23, blue/yellow) to the CAM sensor input (E, 29, green).
View attachment 135146
FOOLED!

You are done! assuming you already dealt with the transmission solenoids and temperature sensor.
the easyest way is to open the AT and unscrew the solenoids and the temperature sensor. now you can pull the whole harness out of the AT and plug it into the car.
put it in a bag or something and strap it to the car. Dont forget that all the solenoids with only one wire need to be grounded! screw them together in pairs and connect them with ring cable lugs to the car. i used the brake line bracket near the tranmission.

If you want a more elegant way or you still need the AT, you also can solder some resistors in place of the solenoids. Note that the 10 Ohm resistors have to be at least 10Watts or they will burn. This is the connector from the CAR, looking onto it as you were the other one wanting to plug into it :)
View attachment 135147
You also could do this at the ECU, but i wont overcomplicate things now.

The only thing missing now, is working cruise control. I already figured out a way to do it, but it would cost arount 100$ to do it.

I hope i could help many guys with my solution and save tons of caashh! :)))
so I followed your instructions and the car starts! Only issue I鈥檓 having is that my cluster is still in 鈥淒鈥 not low/L. Is it just soldering the 2 wires together? On the plug by the old at shifter
 

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Discussion Starter #7
so I followed your instructions and the car starts! Only issue I鈥檓 having is that my cluster is still in 鈥淒鈥 not low/L. Is it just soldering the 2 wires together? On the plug by the old at shifter
yes, you have to connect green/yellow with yellow/green. i just used a piece from a paperclip and put it into the holes of the jack. dont forget to insulate it.
 

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2004 IS300
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yes, you have to connect green/yellow with yellow/green. i just used a piece from a paperclip and put it into the holes of the jack. dont forget to insulate it.
I soldered them together no go. Do you think not having the Red black/red blue wires (underneath) connected together may have an issue with it?
 

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Discussion Starter #9
I soldered them together no go. Do you think not having the Red black/red blue wires (underneath) connected together may have an issue with it?
did you connect tge red/blue to grey? for 2nd gear? the ecu needs both connections done to recognize 1st gear/L
 

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Some great information here that I've been looking for for a while! I'm also relatively new to the forum and have recently swapped my IS with a cd009 manual. I had the auto ecu "tuned" by a company that essentially deleted all of the check engine lights from the swap. That being said I still have the power loss/hesitation with the auto ecu and will definitely be giving this a try. I'm also really curious to know what your solution is for getting cruise control to work.
 

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Some great information here that I've been looking for for a while! I'm also relatively new to the forum and have recently swapped my IS with a cd009 manual. I had the auto ecu "tuned" by a company that essentially deleted all of the check engine lights from the swap. That being said I still have the power loss/hesitation with the auto ecu and will definitely be giving this a try. I'm also really curious to know what your solution is for getting cruise control to work.
Did you use Quantum Auto for the tune?
 

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Discussion Starter #17
Sorry @thatvp , i have found the problem the day i told you i would look it up but it seems my post didnt went through... i posted it from my phone in my garage..
anyway, i have found the mistake! the connection red/blue - grey was WRONG. this gives a "D" feedback to the ECU. cut the connection.
instead connect red/blue to yellow/green! this gives a "2nd" feedback to the ECU. the additional connection inside, at the gear selector, gives a "L" !
please report if you had success, so I can edit the tutorial.
I was trying out a lot as you can imagine, so I got a little bit confused when putting together the tutorial.

@aratk924 this is the first time i hear about "quantum auto". i believed that still nobody managed to get inside the ECU!?

I also drive catless and beat the CEL with a RC circuit, cost: 2 bucks :p
 

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I did, I have mixed feelings as to if it was worth it or not. I have no way to test everything they advertise being able to do, but like I said it still has the issues with hesitation.
Interesting...I haven't heard about problems with them tuning the ECU's. Maybe Brandon is having issues with the ATEMU inside the case or a capacitor that is going bad. Either way I hope it works out for you.

I have a 02' MT that I would like to get tuned by him but I am not sure I want my original ECU to be disturbed...I'm really not willing to make my car undriveable if the ECU turns out not to work. I think I'll use an easily accessible auto ECU and get it tuned with the auto-off and immobilizer removed.
 

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Discussion Starter #19
@thatvp you can also cut 13B (grey) at the ecu and re-route it to 12B AND 15B (green/yellow) if you are lazy to get under the car. thats what i did it. (and why i got confused)
 

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Interesting...I haven't heard about problems with them tuning the ECU's. Maybe Brandon is having issues with the ATEMU inside the case or a capacitor that is going bad. Either way I hope it works out for you.

I have a 02' MT that I would like to get tuned by him but I am not sure I want my original ECU to be disturbed...I'm really not willing to make my car undriveable if the ECU turns out not to work. I think I'll use an easily accessible auto ECU and get it tuned with the auto-off and immobilizer removed.
For those that don't know - quantum auto is a US distributor for the Russian company All4Swap. They're the same ones that actually nanufacture the Atemu that so many other companies resell. I think the ecu tune is a little bit more elegant way of doing the same thing. They claim to do everything in software for the tune, so I doubt I have any hardware issue causing my hesitation but it could be something to look in to.

For my purposes I think it has worked out well, I got my rev limiter raised to 7k, they adjusted the fuel and timing tables which I feel like I can notice a difference from, and I also had them turn off check engine lights for rear 02's and evap codes. Not sure of the legality of this if you live in a place that requires emissions. I'm in tennessee and we have nothing of the sort.

They have a core service that I would probably try next time , you pay a deposit (I can't remember how much) and they'll send you a pre flashed ecu and you send your original back. This eliminates down time and would let you make sure it was going to work before sending yours back. I sent mine in and waited about a month since Yuri was releasing a new version of the firmware.

The reason I say I don't know if mine was worth it was because I still have some issues related to the manual swap. Mainly the throttle response/hesitation that makes it kind of hard to drive with my stage 3 clutch. Also, as some other members of the forum have pointed out, all the fuel/timing map changes are rather basic, and tend to lean the car out a bit. I wouldn't count on it adding any power. The other options they offer probably have the most value.
 
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