RC F (2015-present) Discussion topics related to the RC F model

ECU 2020->2016 swap and launch control

Thread Tools
 
Search this Thread
 
Old 08-20-22, 12:00 AM
  #1  
Movelexus
Pit Crew
Thread Starter
 
Movelexus's Avatar
 
Join Date: Jan 2022
Location: CA
Posts: 187
Received 185 Likes on 81 Posts
Default ECU 2020->2016 swap and launch control

Obtaining the RR-racing tune and supercharger kit on 2017+ models involves swapping to the 2016 model year ecu. Does this entail also losing launch control on the car after moving from the 2020 ecu to 2016 ecu?
Old 08-20-22, 12:21 AM
  #2  
05RollaXRS
Lexus Test Driver
 
05RollaXRS's Avatar
 
Join Date: Oct 2005
Location: Calgary, AB
Posts: 9,961
Received 2,504 Likes on 1,802 Posts
Default

I don't know how different launch control is from the launching method available in the 2015 - 2019 RCF? I have done this many times while testing with Dragy without the launch button and it effectively does the same thing.

This is how I do it:

1 - Traction control off (hold it down for 3 seconds)
2 - Put the car in SPORT+ mode
3 - Auto mode or manual mode. Good thing about auto mode is, I don't slam into the rev limiter like in manual mode so auto mode is more consistent in times.
4 - Push brake down firmly and hold it down.
5 - Push the gas pedal down until the revs slowly start to rise. The car will start to tighten up and will feel it slightly compressing.
6 - Once revs rise to 1500 - 1700 rpm, hold it there for 2 - 3 seconds
7 - Let go of the brake and slam the throttle down. The car will launch forward.

Last edited by 05RollaXRS; 08-20-22 at 12:40 AM.
The following 4 users liked this post by 05RollaXRS:
1wacko (09-08-22), konichiwa3 (08-20-22), Movelexus (08-22-22), SideOfRice (08-20-22)
Old 08-20-22, 03:05 AM
  #3  
Movelexus
Pit Crew
Thread Starter
 
Movelexus's Avatar
 
Join Date: Jan 2022
Location: CA
Posts: 187
Received 185 Likes on 81 Posts
Default

Originally Posted by 05RollaXRS
I don't know how different launch control is from the launching method available in the 2015 - 2019 RCF? I have done this many times while testing with Dragy without the launch button and it effectively does the same thing.

This is how I do it:

1 - Traction control off (hold it down for 3 seconds)
2 - Put the car in SPORT+ mode
3 - Auto mode or manual mode. Good thing about auto mode is, I don't slam into the rev limiter like in manual mode so auto mode is more consistent in times.
4 - Push brake down firmly and hold it down.
5 - Push the gas pedal down until the revs slowly start to rise. The car will start to tighten up and will feel it slightly compressing.
6 - Once revs rise to 1500 - 1700 rpm, hold it there for 2 - 3 seconds
7 - Let go of the brake and slam the throttle down. The car will launch forward.
This is interesting and not exactly like the sequence on the 2020+ launch mode. I can enable it and completely depress the gas pedal to full throttle prior to releasing the brake pedal. It holds it at ~1800-2000 rpm until brake pedal is depressed. The car does “tighten and compress” however. I wonder if that is partly lost when disconnecting active dampers.
Old 08-20-22, 05:07 AM
  #4  
SideOfRice
Driver
 
SideOfRice's Avatar
 
Join Date: Feb 2022
Location: PNW
Posts: 81
Received 50 Likes on 29 Posts
Default

Originally Posted by 05RollaXRS
I don't know how different launch control is from the launching method available in the 2015 - 2019 RCF? I have done this many times while testing with Dragy without the launch button and it effectively does the same thing.

This is how I do it:

1 - Traction control off (hold it down for 3 seconds)
2 - Put the car in SPORT+ mode
3 - Auto mode or manual mode. Good thing about auto mode is, I don't slam into the rev limiter like in manual mode so auto mode is more consistent in times.
4 - Push brake down firmly and hold it down.
5 - Push the gas pedal down until the revs slowly start to rise. The car will start to tighten up and will feel it slightly compressing.
6 - Once revs rise to 1500 - 1700 rpm, hold it there for 2 - 3 seconds
7 - Let go of the brake and slam the throttle down. The car will launch forward.
Wait, what? This is new to me thanks! I’m gonna have to try it now.

Sorry OP I have no useful information regarding your question but found Rolla’s response interesting as it’s new news to me regarding 2015 - 2019 launch. Hope you find an answer
Old 08-20-22, 08:26 AM
  #5  
05RollaXRS
Lexus Test Driver
 
05RollaXRS's Avatar
 
Join Date: Oct 2005
Location: Calgary, AB
Posts: 9,961
Received 2,504 Likes on 1,802 Posts
Default

Yeah, it is the same 1800 rpm stall limit. I just never went higher thsn 1300 - 1500 rpm. Regarding "compress snd tighten", it simply happens due to.oppsosing forces of the rear wheels wanting to accelerate while brakes are stopping the car eith force in the opposite direction

Originally Posted by Movelexus
This is interesting and not exactly like the sequence on the 2020+ launch mode. I can enable it and completely depress the gas pedal to full throttle prior to releasing the brake pedal. It holds it at ~1800-2000 rpm until brake pedal is depressed. The car does “tighten and compress” however. I wonder if that is partly lost when disconnecting active dampers.
Old 09-07-22, 10:45 PM
  #6  
Movelexus
Pit Crew
Thread Starter
 
Movelexus's Avatar
 
Join Date: Jan 2022
Location: CA
Posts: 187
Received 185 Likes on 81 Posts
Default

Attempted running with the 2016 ECU tonight and so far no success. Car ran for 1-2 seconds then engine shut down. Now it cranks but won't start. Will post more once I have more information. Pinout on my DLC3 connector doesn't match the sequence Rafi sent me for ECU communication ID registration so I haven't able to attempt that yet. My pin 13 is unwired. I've read that sometimes TC can be in pin 12 or 14 as well but don't want to risk causing issues. I asked a friend that works in a Lexus dealership shop for info... he will get back to me tomorrow. Also asked Rafi his opinion.









Last edited by Movelexus; 09-07-22 at 11:17 PM.
The following users liked this post:
05RollaXRS (09-07-22)
Old 09-07-22, 10:46 PM
  #7  
Movelexus
Pit Crew
Thread Starter
 
Movelexus's Avatar
 
Join Date: Jan 2022
Location: CA
Posts: 187
Received 185 Likes on 81 Posts
Default

Had a fun time swapping it out though!


The following users liked this post:
05RollaXRS (09-07-22)
Old 09-07-22, 11:45 PM
  #8  
Movelexus
Pit Crew
Thread Starter
 
Movelexus's Avatar
 
Join Date: Jan 2022
Location: CA
Posts: 187
Received 185 Likes on 81 Posts
Default

Checked the codes with the Carly device. Seems my main issue is the immobilizer so if I can run the sequence described in Rafi's document it probably will be fine. Height control RL (Rear Left) actuator circuit is worrying. The car has felt very stiff in all modes so it's not impossible it's stuck in S+ mode? Would explain recent behavior of the suspension and ride quality. I was just blaming this on track edition tuning. Won't matter once coilovers go in but I'll likely get it checked before putting the coils in as the car is still under warranty. (We'll keep this ecu swapping on the downlow when I go see Lexus)






Old 09-08-22, 03:15 PM
  #9  
05RollaXRS
Lexus Test Driver
 
05RollaXRS's Avatar
 
Join Date: Oct 2005
Location: Calgary, AB
Posts: 9,961
Received 2,504 Likes on 1,802 Posts
Default

Hopefully, RR racing will assist. They are pretty good as I had some difficulty doing my remote RR racing ECU, but it ended up all working out
Old 09-08-22, 04:20 PM
  #10  
Movelexus
Pit Crew
Thread Starter
 
Movelexus's Avatar
 
Join Date: Jan 2022
Location: CA
Posts: 187
Received 185 Likes on 81 Posts
Default

Originally Posted by 05RollaXRS
Hopefully, RR racing will assist. They are pretty good as I had some difficulty doing my remote RR racing ECU, but it ended up all working out
Rafi has been assisting!

We found out newer model years need Techstream to perform the ECU communication ID registration. I need a tactrix 2.0 cable or the mongoose MFC3 cable that Toyota uses. I ordered the MFC3 cable + 1 year techstream subscription from Toyota today and selected overnight shipping. I called them to make sure it would be shipped today and they told me it definitely wouldn't as they are backordered 6 months. I ordered a price gouged MFC3 Mongoose-Plus cable from Amazon instead. It will arrive Saturday.

On the Toyota TIS looking at the wiring diagram it shows the TC pin is connected on the 2020 models but the connection isn't physically there. Either they started not installing the wire for security purposes on more recent models and omitted updating the wiring diagram OR they didn't manufacture my car properly OR it was tampered with.

Here is the diagram and sequence for 2020 model year.





Old 09-10-22, 10:56 PM
  #11  
Movelexus
Pit Crew
Thread Starter
 
Movelexus's Avatar
 
Join Date: Jan 2022
Location: CA
Posts: 187
Received 185 Likes on 81 Posts
Default

I was able to start the engine with the 2016 ecu with some issues.

-launch control now turns on “snow” mode and lights that light up in the instrument cluster.
-“trac off” is on in the instrument cluster
-can’t select eco/sports s/sports s+ car appears to be stuck in normal mode.

car gives a U0100 ecm/pcm communication code causing check engine to stay on. This persists after clearing codes with techstream. Rafi said this usually goes away after a battery disconnect for ~15 mins but I got this information after swapping back to the 2020 ECU. Will try again in the morning and perform this step.

No issues at all after swapping back to 2020 ECU and registering it with the 30 min active test. Car wouldn’t start on 2020 ecu prior to doing active test to register.




The following users liked this post:
vraa (09-10-22)
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
gFREAKy
IS - 2nd Gen (2006-2013)
4
04-07-15 12:40 PM
Dj_AmtraX
IS - 2nd Gen (2006-2013)
9
04-19-07 02:00 AM
Dinomon
RX - 2nd Gen (2004-2009)
11
03-14-07 03:03 PM
rscott
Performance & Maintenance
12
03-19-05 12:08 AM



Quick Reply: ECU 2020->2016 swap and launch control



All times are GMT -7. The time now is 02:49 AM.