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2004 IS300
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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
Can confirm! It is in fact the the RED/BLUE to YELLOW/GREEN wire to put it into Low. Just soldered it together.
 

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@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)
Did you ever figure out how to get the cruise control working again? I just started back at college and the drive is killing me. You had suggested wiring the cam/crank signal to what used to be the transmission output shaft speed sensor. Will this work for the cruise control? If I'm correct in my assumptions - as long as the signal linearly increases with speed it shouldn't really matter where it comes from. We don't have a torque converter to worry about anymore so engine speed is fixed to wheel speed.

Alternatively, would it be possible to wire the abs speed output similarly to the output shaft speed sensor?

Also, I'm not too concerned with the clutch switches. I have the xcessive pedal bracket which doesn't have provisions for the factory switches. I never wired up the neutral safety switch and haven't had any issues. It's pretty easy to avoid starting the car in gear, I assume it'll also be pretty easy not to push the clutch pedal with the cruise engaged. Eventually I want to tee into my clutch line with a brake light pressure switch, I'll do pretty much anything to avoid working under the dash.

Any help is appreciated, Im driving back Monday so hopefully I can get this wired up this weekend. Thanks!
 

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Alright, today I had some free time and started going through the wiring. I wired up the shifter in the car for low (yellow/green to green/yellow) and followed the revised instructions for the transmission plug for 2nd gear (red/blue to yellow/green). No dice. The cluster doesn't go into L - I haven't checked techstream to see if 2nd gear shows it is engaged but I'm doubtful. You had also posted instructions to do this at the ecu plug which I also gave a try. This didn't work either. Pin 13B is not gray on my harness, it is yellow/red and the pinout I am following is listed as the cruise control clutch switch which seems to be unrelated. B12 and B15 seem to be correct though. They are green/yellow and yellow/green and are listed as A/T indicator 2 and Trans Control Switch L which seems to be correct with what we are doing here.

I'd like to know what I'm doing wrong here. The fact that some of my wiring colors are different doesn't exactly ensue confidence. I assume it could also be a possibility that since my auto ecu has been "tuned" to make it manual that they could have turned off features like the gear selection inputs from the shifter and from the transmission. I've searched around for documentation and really haven't been able to find anything. If any of you have ideas I'd be willing to try them. If it doesn't work out I guess I will just end up buying a manual ecu, but I would really like to avoid doing so. Any and all help is appreciated!
 

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Discussion Starter #24
As I remember CC worked with the crank sensor wired to transmission input/output shaft RPM. however, as the crank trigger has too many teeth (36/rev) the ECU seems to detect too high input shaft rpm and wont let you rev past 5k RPM. this is why I used the CAM sensor, it has 2-3 teeth, it spins half the speed, so you end up with 1-1.5 tooth/rev. this seems to be not enough to let the CC start. you would need sth like a yellow box tach converter so you can multiply the signal. technically ABS would work, as it is VR too, but 48teeth/rev x diff ratio 3.9 or 3.7 would be way too high. the other thing is that CC only works in D, so you would again have no good throttle response.
As it worked fine exept the missing CC and it was a temporary solution until I got my standalone it was enough for me.
You can check me out on instagram and see the working CC with my standalone :)
The wiring instruction at the ECU I gave you was assuming you let the wiring at the trans connector the way it was !
The Key is to give 15B and 12B +12V. while 13B has NO 12V+, this would put it in D! I attached a picture so you can see what i mean.
 

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Discussion Starter #25
When I did all of this, I also wondered wether the ECU still cuts power because it gets the same signal for transmission input and output shaft rpm. this would be logical to me because in 1st gear it should in fact expect a gear ratio of 3.357. so a 1:1 ratio would mean there is exessive torque converter slip. but then there is also the question if input and output tooth amount are the same. As I had no CEL and the power delivery was finally smooth, i didnt bother.
 

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When I did all of this, I also wondered wether the ECU still cuts power because it gets the same signal for transmission input and output shaft rpm. this would be logical to me because in 1st gear it should in fact expect a gear ratio of 3.357. so a 1:1 ratio would mean there is exessive torque converter slip. but then there is also the question if input and output tooth amount are the same. As I had no CEL and the power delivery was finally smooth, i didnt bother.
Alright, I got it wired up last night and drove back to school two and a half hours this morning. Car feels so much better. I was unaware the cruise control only works in drive so I didn't bother hooking up the cam/crank sensor for that since it's not throwing a code for me on my tuned ecu. Full disclosure - when I originally did the swap I cut off the original transmission harness way back close to the intake manifold, so in the mess of wires I failed to realize that there are two sets of red/blue - one for one of the solenoids, and one that is the common positive for the range switch. I didn't put it together until last night that this was the wire that I had extended all the way down to my reverse switch. That wiring diagram you provided really helped with this. It's all wired up in L now and is so much more responsive. I think I can live without the cruise control with the throttle feeling as good as it does. Thanks so much again for the diy and for the help along the way!!
 

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'03 MT BO SportX & '02 White SportX
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Hey - We connected on instagram a few weeks ago.

When I first did my manual swap, I thought I had a working MT ECU, but turns out it was broken. So I'm left with my AT ECU. Last year, I followed the guide by @Curran , Auto to Manual Swap, Wiring, Ecu, CC, NSS, CLSW, Trac, Snow, now smogged in CA

So far I have:

• Cut the red/black wire (connector D, pin 5) on the ecu connector. (ECU doesn't know it's in reverse)
• Cut and soldered the green/yellow wire with the yellow/green wire under the shifter (Tell ECU it's in Low Gear)
• Extended both the yellow/green wire and the red/blue wire from the big AT Plug (Tell ECU it's in 2nd gear) into the Cabin and connected it to a simple switch (Pictured below).... you may see where this is going...

137243


However, since I followed @Curran's Guide during the initial swap, that means I've done the following wiring on the clutch Pedal:

NEUTRAL SAFETY SWITCH
Neutral safety switch. Reroute wire #6 and #9 to the clutch pedal. connect wire 6 & 9 to Neutral safety switch. Part number 90980-10825

CRUISE CONTROL
Cruise control clutch switch. Cut B13 from ecu and wire to cruise control clutch switch, then to driver side fuse box harness 1A pin 4. Part number 90980-10906.

This causes the ECU to think the transmission is in Drive so as long as the clutch is not being depressed.

So when I have the yellow/green wire and the red/blue wire connected via the switch (which I'll eventually install in the blank space next to the coin holder), the ECU thinks the transmission is in both "Drive" and "Low" simultaneously. (See Picture)

137244


I assume this throws some error codes but I don't have the gear to see those.

Sorry @thatvp , 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.
Per this post ^, I also extended the red/blue and grey wires into the cabin and connected via another switch, but that connection wasn't toggling "Drive" on the combometer as you said it would.

I think this is because of the wiring I did in accordance with @Curran's guide - "Cut B13 from ecu and wire to cruise control clutch switch, then to driver side fuse box harness 1A pin 4." So this means when I slightly depress the Clutch, the Combometer shows that the car is no longer in "Drive".

All of this to say, I think I'm gonna interrupt the circuit for the Cruise control safety switch with another switch (mounted next to the first switch by the coins) so that I can toggle the car being in Drive for when I want to use Cruise control (once I buy the Yellowbox Tach converter).

I'd like to have my cake and eat it too so to speak - good throttle response most of the time while having functional Cruise Control for longer trips.

Lemme know if you think this will work.

- David
 

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Discussion Starter #28
today I hooked up the VVTI solenoid to the stock ECU and made some runs and read the VVTI angles from the stock ECU with my standalone.
I found out sth really interesting:
In neutral the VVTI is completely dead! some people hook it up like this, which also throws no CEL, but this is the reason for the shitty power delivery!!
rewired it like before and VVTI was working again! this is why you should follow my instructions and wire it up like its in L!
I will post the stock VVTI map in my build thread.


@Dteo827 you could wire it to a single "switching type" switch, no on/off switch. But Im still not sure if it will work. the problem is that the ECU is constantly monitoring input/output shaft RPM. If you hook up the yellowbox you can simulate it to mimic a certain gear, but i am not really shure what happens when the ecu tries to change gear. I just cant remember if cruise control worked with the shaft sensor inputs wired to the crank sensor. i think it did, it only didnt want to rev over 5krpm. you can just simply try it out. if It works, then you can buy the yellowbox and put it in between the crank sensor and the shaft speed input and slow the signal down by 1/4 or so.
if it works i can help you with a prettier switch solution.
 
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