A340 Paddle Shifters

I mainly just want to follow this thread, but your point is valid; Why the hell did my based model Outback with a CVT have paddle shifters? Why does anyone do anything? All I'm saying is that looks complicated AF. There is no way I wouldn't give up on that project before completion. I'm in!

 

I wont lie, I came into this hoping for an out of the box solution, and didnt intend to get this deep. I do like a challenge though, and my background is in control systems software engineering which lends fairly well to the task. But I know very little past residential electrical, and finding information on this project has been very difficult because as people said, it is not exactly a common request. I am also blessed enough to be in a situation where this is not my only vehicle, so if I screw something up I am not out of a ride to work. If I did not have that luxury, I would not dare start poking at ECM wires.

The project is still far from done, so there is still ample opportunity for me to give up! lol thanks for following along, and any suggestions are welcome.

 

I built and tested the step up converter on a range of supply voltages and it worked. It was a very simple circuit with a IRLZ44N transistor and a 10kOhm resistor, so I am pleased that it will be easy to replicate on other channels (although I will only have 2 or 3 different 12V outputs if all goes according to plan).

The short and open codes for the 2 shift solenoids are P0973, P0974, P0976, and P0977. It checks that the resistance range is between 8 Ohms and 100k Ohms, which is a big range! Normal operating resistance is 11-15 Ohms across the physical solenoids in the transmission at typical temperature. SLU has similar checks, and it has a standard resistance of 5.1-5.5 Ohms. Should be easy to fake that out on a parallel circuit if the master switch is set to manual mode. Looks like the CEL resets after 1-2 drives anyway, so I have lots of attempts to get it right.

Added logic in for the orange and red shift lights into the code. Ordered some prototyping board to start cleaning up the circuits, and will be cleaning up the circuits within the next couple weeks. I think I am about ready to start testing signals from the ECM taps! Might be the last update in a bit as I will be waiting for the boards and have other commitments coming up, but if I get a moment I want to upload some of the source material I am utilizing in the meantime.

 

Okay, did some testing with the actual ECM today, and the solenoids are working as expected, but the tachometer signal/ pulseIn() function was not. It looks like with 2012-2015, the comms with the tach are strictly CANbus only. So, my options are to a) read in via CANbus, b)attempt to create a new formula for the transmission output shaft sensor that reads in to the ECU, or c) ignore and have no speed safety lockout like a real manual transmission. I am brainstorming, but I think I am going to try to go with option B. Seems like the safest with the least amount of rework.

Solenoid diagram and pinout from ECM (for later Gen 2s only, earlier Gen 2s use only 4 harnesses):


I also got some PCB in, and I am working on simplifying the circuits. I have notoriously unsteady hands, so my soldering is usually abysmal, fair warning. I think for proof of concept and ease of replacement in the early stages, I will probably make each component on its own small circuit board. That way if something fails, I can remove it without taking everything apart. If it does work, I will probably make a second version that is more clean/ permanent (or more realistically ask a friend who doesn't solder like a middle-schooler).

A functional test example on PCB of a linear buck/ boost converter:


For very early testing with the actual circuits, I will probably ignore the speed lockout, but I feel like having it is a must for me if I am ever going to actually use it for a purpose other than low-speed tests around the neighborhood.

I have also come up with a new display idea that requires less wires to be routed and fits in a much smaller area (possibly a gauge pod). I am going to use a digital 7-segment, single digit display. Beside it, I will have 2 LEDs, orange and red for shift indicators. So basically my output will be just a digit for gear number, a dot to indicate manual mode is active, and 2 small LEDs, rather than using the full 16x2 LCD screen in the 'final product.'


Once I get the main circuit and some of the auxiliary components soldered, I will try to take it for a low speed moving test. Then if that works, next steps are speed lockout and making things look presentable (container for piggyback controller and circuits, display mount, paddles on wheel, etc).

 

Breakthrough! Was successfully able to read in engine speed. Had some issues with the CANbus upload speeds/ baudrate alignment, but got them sorted out fairly well. I am using a conservative high-pass filter to eliminate any noise that may come through under 500 rpm and interfere with the signal. The signal is accurate to about 50 ms scans, which is probably plenty fast considering the shifts themselves take nearly a whole second from the transmission (transGo valve shift kit in the future?).

If anyone uses this method, it is worth noting that the controller shield does not fit a 2560R3 arduino, and you will have to edit the 'default' library to use pins 50-53 instead of pins 10-13 for SPI comms. I wont go into detail on this here since it is pretty specific to my particular scenario, but if anyone happens to get confused on this step in their own project, I'd be happy to help if you reach out.

I believe I now have all signals working, and I just need to throw them into one singular routine and package things more neatly. I'd say I am reaching the end of the development stage of the project!

 

I have started to assemble the electronics all together in a final box and decided on placements within the truck:

I will be putting the auto/man toggle switch on the left of my wheel (near the fog light button, etc). The electronics box will go in the center console/ armrest as there is already holes that lead to the runway under the shifter and up to the dash right under the felt floor-piece. That leaves in front of my cupholder open for future CB radio installation. For now I will put the gear readout and shift lights in one of the auxiliary button sections by the USB port until I get a pod cluster. Not an ideal location for forever, but I can see the lights in my peripheral vision and it is an easy location for the medium term without having to drill holes in any dash panels or buy anything new. Good enough for getting used to the set up and making adjustments.

Long term, I will be using a pod set up, as I just picked up a URD supercharger kit recently. I will probably be installing in early-mid 2026 after a couple trips that I have planned, and installing a transgo valve kit for faster shifts (less slippage/wear with boost). I will be installing pods for AFR and Boost Pressure during that project, so when the time comes I will extend those connections up above the steering wheel where it makes more sense.

Once everything is in place, I will upload some pics of it coming together.

 

Here is a photo of the holes under the felt that I am running the signal wires through up the shifter console to the dash:

Here is the general layout of the final enclosure... will fix the main circuit boards to the container after I have run it for a while. Want to have the flexibility to remove and troubleshoot if needed for a bit, but also dont want connections jostling around for long. Enclosure box hides nicely in the arm rest with lots of room to spare. Going to make sure the transistors have some breathing room in case they get hot.


Here is what it looks like with the console removed and where I am running the wireways:


Location of the 4PDT switch that will also toggle the mode from man/ auto:


I was in the process of running all the wires from the ECU, Switch, and piggyback controller when it started storming despite what the weather called for. Was hoping to finish up this weekend, but the truck may have to stay in a bit of disarray for a bit longer. Should come together and look pretty darn close to stock.

My temporary gear indicator and shift light is... not pretty. Luckily it wont be the final resting place for it and will be getting updated in a year or so. For medium-term trial purposes, it'll be good enough.

 

Well the rain stayed away long enough to make some progress, but not long enough to finish. Here are some status update pics.

Shift Lights and Gear Indicator (with wires dangling, still work in progress). Arduino is currently powered by the stock USB port, which is nice because it is fused, low voltage, and shuts off when the truck does! Will make this prettier, but I also need to be able to pull out extra length of the USB for future software updates:


Manual/ Auto Switch now hooked up and functional:


How the little enclosure fits in the arm rest console. Going to run plastic tubing along the wires so I dont get issues with vibrations/ rubbing:


This last picture is not my picture, but I found a guy who added paddles to his Tundra (same steering wheel, already has sport sequential shifting on the auto stick) so this is the same look I will be going for:


Not too much left to do, but it was super cold out, I was losing light, and I wanted to be done for the day. No point in doing this stuff if you don't enjoy it!

Getting used to tapping ECU wires now, because the Supercharger kit requires a decent bit of that!

 

Insane. I thought I had a decent bit of electronics knowledge but you are on another level.

May I ask your method for tapping wires? Also how does one get started with Arduino? I've always been interested but stayed away because C++ is not my strong suit to say the very least.

 

I appreciate the kind words! The most important feature to me is that the switch puts all ECU connections right back to stock configuration. So if some Arduino connection comes loose, there is a software bug, or whatever the case may be, I can just flip the switch and pretend nothing changed until I get home to look at it.

I have found that the most reliable method for automotive applications is properly-gauged crimp T-Taps, at least in my experience. Everyone has an opinion on what worst best for them, but they are very secure and vibration proof.

For Arduinos, you can get a variety of starter kits on ebay or Amazon in the ~$50 range that have lots of accessories for projects and testing. You can get just the controller itself for $5-15, depending on what model you want. If I wanted to save space and spend money, I'd get a smaller controller with less inputs just for this project.

Don't let any programming language scare you. Logic is logic. If you can write pseudo-code on a paper, the rest is just wrestling with syntax and there are tons of resources online that can help for free. I do write code for a living, but for this project all of the code is pretty basic. I can post a working revision of the code, but it is a draft and not fully flushed out yet so I can't recommend using it.

Actually, probably good to have a disclaimer in general... I am not responsible for anyone who tries to do this! lol

 

CODE FOR TESTING PURPOSES AND IS NOT A FINAL REVISION. DO NOT USE IN THIS STATE.

//Transmission controller
#include<Canbus.h>
#include<defaults.h>
#include<global.h>
#include<mcp2515.h>
#include<mcp2515_defs.h>
#include<Wire.h>


volatileint active;
//4th gear is safest to start in if all else fails. Engine can't overrev in 4th
volatileint currentGear = 4;
//Set lockup status to engaged to force unlock at first change unless later read otherwise, for safety
volatileint lockupStatus = 0;
//Solenoid signals
constint solenoid1 = 40;
constint solenoid2 = 41;
constint S1read = 42;
constint S2read = 43;
//Control signals
constint masterSwitch = 44;
constint upButton = 45;
constint downButton = 46;
int counter = 0;
unsignedlong disarmTimer;
unsignedlong sensitivity = 500UL;
int buttonsArmed = 0;
int firstRun = 1;
int firstInactiveRun = 1;
//Data will be temporarily stored to this buffer before being written to the file
chartachBuffer[64];
int tachTranslate;
int SafetyLock = 0;
unsignedlong EngineSpeedRPM = 0;
//Pod Display Signals
constint segA = 23;
constint segB = 22;
constint segC = 24;
constint segD = 25;
constint segE = 26;
constint segF = 27;
constint segG = 28;
constint segH = 29;
constint orangeLED = 32;
constint redLED = 33;


voidsetup()
{
//Initialize serial
Serial.begin(9600);
//Initialize relays in OFF position
digitalWrite(solenoid1, LOW);
digitalWrite(solenoid2, LOW);
//Set pins to output mode
pinMode(solenoid1, OUTPUT);
pinMode(solenoid2, OUTPUT);
//Pins for switches
pinMode(masterSwitch, INPUT_PULLUP);
pinMode(upButton, INPUT_PULLUP);
pinMode(downButton, INPUT_PULLUP);
//Pins for gear sensing
pinMode(S1read, INPUT);
pinMode(S2read, INPUT);
//Pins for numeric gear display
pinMode(segA,OUTPUT);
pinMode(segB,OUTPUT);
pinMode(segC,OUTPUT);
pinMode(segD,OUTPUT);
pinMode(segE,OUTPUT);
pinMode(segF,OUTPUT);
pinMode(segG,OUTPUT);
pinMode(segH,OUTPUT);

//Initialise MCP2515 CAN controller at the specified rate
Canbus.init(CANSPEED_500);
delay(1000);

}

voidloop()
{
//Serial counter to watch loop times
Serial.println(counter);
//Master switch goes between auto and manual

//digitalWrite(redLED,HIGH);

if(digitalRead(masterSwitch) == 1){
active = 1;
digitalWrite(segA,HIGH);
}
else{
active = 0;
digitalWrite(segA,LOW);
}

//Active 0 is automatic/factory passthru mode
if(active == 0){
if(firstInactiveRun == 1){
//Ensure all relays are off on first loop since arduino is still connected
digitalWrite(solenoid1, LOW);
digitalWrite(solenoid2, LOW);
firstInactiveRun = 0;
//FirstRun set to 1 syncs manual mode to the current gear when initially switching to manual
firstRun = 1;
}
//Take input and discard to avoid queueing changes
char ser = Serial.read();
//Monitor shift solenoids for gear and lockup clutch
determineGear();
//in Auto, dont show shift lights
digitalWrite(redLED, LOW);
digitalWrite(orangeLED, LOW);
}

//Active 1 is paddle shift manual mode
if(active == 1){
if(firstRun == 1){
//Activate relays to match what automatic/passthru mode was doing on the previous loop
callGear(currentGear);
//FirstInactiveRun forces all relays off when initally switched to auto mode
firstInactiveRun = 1;
firstRun = 0;
}

//read in CANbus data and filter
Canbus.ecu_req(ENGINE_RPM, tachBuffer);
tachTranslate = atoi(tachBuffer);

if(tachTranslate > 500){
EngineSpeedRPM = tachTranslate;
}
delay(10);

//See if safety lockout is needed to prevent downshift
speedCheck();
//display shift light based on engine speed
//indicatorLight();

//ButtonsArmed is a millis-based debounce system
if(buttonsArmed == 1){
if(digitalRead(upButton) == 1){
upShift();
buttonsArmed = 0;
disarmTimer = millis();
}
if((digitalRead(downButton) == 1) && (SafetyLock == 0)){
downShift();
buttonsArmed = 0;
disarmTimer = millis();
}
}
else{
//If not armed, check disarmTimer to re-arm
if((millis() - disarmTimer) >= sensitivity){
buttonsArmed = 1;
}
}
}

//Counter only functions as performance metric. Loops at 1000 to prevent overflow
counter++;
if(counter >= 1000){
counter = 0;
}
}

//The following subs activate specific solenoids to shift to the desired gear. There are 2 shift solenoids.
voidfirstGear()
{
digitalWrite(solenoid1, HIGH);
digitalWrite(solenoid2, LOW);
currentGear = 1;
display1();
}
voidsecondGear()
{
digitalWrite(solenoid1, HIGH);
digitalWrite(solenoid2, HIGH);
currentGear = 2;
display2();
}
voidthirdGear()
{
digitalWrite(solenoid1, LOW);
digitalWrite(solenoid2, HIGH);
currentGear = 3;
display3();
}
voidfourthGear()
{
digitalWrite(solenoid1, LOW);
digitalWrite(solenoid2, LOW);
currentGear = 4;
display4();
}

//upShift and downShift paddles for sequential gearchanges
//prevents shifting above 4th or below 1st
voidupShift()
{
if(currentGear < 4){
currentGear++;
}

switch(currentGear){
{
case2:
secondGear();
}
break;
{
case3:
thirdGear();
}
break;
{
case4:
fourthGear();
}
break;
}
}

voiddownShift()
{
if(currentGear > 1){
currentGear--;
}

switch(currentGear){
{
case1:
firstGear();
}
break;
{
case2:
secondGear();
}
break;
{
case3:
thirdGear();
}
break;
}
}

//Check engine RPMs to make sure downshift will not cause overrev
voidspeedCheck()
{
if(currentGear == 2 && EngineSpeedRPM >= 2803)
{
SafetyLock = 1;
}
elseif(currentGear == 3 && EngineSpeedRPM >= 3391)
{
SafetyLock = 1;
}
elseif(currentGear == 4 && EngineSpeedRPM >= 3677)
{
SafetyLock = 1;
}
else{
SafetyLock = 0;
}
}

//determine urgency and corresponding LED color based on RPM
voidindicatorLight(){
if(EngineSpeedRPM > 5300){
digitalWrite(redLED, HIGH);
digitalWrite(orangeLED, LOW);
}
elseif(EngineSpeedRPM > 4900){
digitalWrite(orangeLED, HIGH);
digitalWrite(redLED, LOW);
}
else{
digitalWrite(redLED, LOW);
digitalWrite(orangeLED, LOW);
}
}

//Monitor voltage of solenoid 1 and 2 wires to see what the factory computer is doing
//2 solenoids, 2 states each = 4 gears
voiddetermineGear(){
if(digitalRead(S1read) == 1){
if(digitalRead(S2read) == 1){
currentGear = 2;
}
else{
currentGear = 1;
}
}
else{
if(digitalRead(S2read) == 1){
currentGear = 3;
}
else{
currentGear = 4;
}
}
}

//Used for synchronizing auto to manual mode on first switchover scan
voidcallGear(intoption){
switch(option){
{
case1:
firstGear();
}
break;
{
case2:
secondGear();
}
break;
{
case3:
thirdGear();
}
break;
{
case4:
fourthGear();
}
break;
}
}

voiddisplay1(){
digitalWrite(segB,HIGH);
digitalWrite(segC,HIGH);
digitalWrite(segD,LOW);
digitalWrite(segE,LOW);
digitalWrite(segF,LOW);
digitalWrite(segG,LOW);
digitalWrite(segH,LOW);
}

voiddisplay2(){
digitalWrite(segB,LOW);
digitalWrite(segC,HIGH);
digitalWrite(segD,HIGH);
digitalWrite(segE,LOW);
digitalWrite(segF,HIGH);
digitalWrite(segG,HIGH);
digitalWrite(segH,HIGH);
}

voiddisplay3(){
digitalWrite(segB,HIGH);
digitalWrite(segC,HIGH);
digitalWrite(segD,HIGH);
digitalWrite(segE,LOW);
digitalWrite(segF,LOW);
digitalWrite(segG,HIGH);
digitalWrite(segH,HIGH);
}

voiddisplay4(){
digitalWrite(segB,HIGH);
digitalWrite(segC,HIGH);
digitalWrite(segD,LOW);
digitalWrite(segE,HIGH);
digitalWrite(segF,LOW);
digitalWrite(segG,HIGH);
digitalWrite(segH,LOW);
}

 

Wow, thank you!

 

Yeah, if you ever decide you want to start on a coding project and need help, just let me know!

 

this is awesome!!
impressive work!

subbed for interest

 

Thanks, I appreciate the support! Please let me know if you have any suggestions.

Once I finish the paddles, it will be a trans cooler and shift valve kit (stock auto shifts take nearly a whole second from signal to full engagement), then the supercharger goes on.

 

I am seriously impressed
And happy that I understand most of it

 

Easter weekend just started for me, so I am hoping to wrap up this project by end of day Sunday! May be easier said than done in the time between traveling to see family, etc.

Anyone have ideas for how to mount the paddles to the wheel? I did manage to get in touch with the person whose reference photo I included previously on a Tundra wheel, and he had used insert nuts, but I didnt glean too much more info than that. I am wondering if I should use some sort of expanding tree clips paired with a VHB adhesive in the holes, or an epoxy? I really want to make sure I have a good plan before altering the material on the wheel. Dont want to botch that, and obviously dont want the paddles to be floppy and loose.

The wires are run to the clockspring on the column, but I have yet to take the wheel off. Gotta disconnect the battery anyway for the last round of ECM/ solenoid signal tie-ins, so I will yank off the wheel probably on Saturday when I do that.

 

Check these out. Obviously, some custom work would be required, but from what I’ve seen, many Toyotas share the same steering shaft spline count. It might be possible to adapt the OEM paddle shifters from the new A90 Supra for your setup? Are you trying to keep your factory steering wheel?

 

I am not super stuck on having the factory wheel, but I am stuck on retaining an airbag. I also already have the corolla iM paddles that I have been testing with, so it would be nice to use those if possible. But something like you suggested would probably be a better off the shelf solution than mine, if I could make it work with my wheel or at least a wheel with an airbag!

 

Got a couple hours of work done on the project. Wheel is off and clockspring is wired and tested. Paddles are working through the wheel and changing gears.

1 = downshift, 2 = 5V/ ground (depending on how you wrote the code), 3 = upshift



Here are the corresponding harness pins on the column side of the clock spring. This pic came out way worse, so I will just say the pins used are A, D, and E for wires 1, 2, and 3 respectively.

Worth noting that for some reason this harness does not come with the female crimp terminal connections, so you will have to add pinouts yourself.

Here are some drafts of wiring to the solenoids/ ECM to the main microcontroller from earlier in the process. They may be slightly different now, but they are still substantially correct for someone to reference. If you do your own version, you'll probably be doing it slightly differently anyway.


Drafts of circuits for voltage regulation, where resistors are slightly adjustable based on the drop/boost you want to achieve:


And as if I wasnt already in too deep, my steering wheel is now sitting in the house. Remember that before doing anything with the ECM or airbag, always disconnect battery and let it sit for awhile to discharge any capacitance. Luckily the weather was nice so I got to take my fun car out to visit family, but I will need the steering wheel back on very soon!


Still not sure how I am going to mount these paddles. Honestly, a smart person probably would have started with that.... I am running out of time to keep kicking that can down the road!