Torque Convertor lock up instal

[BigFoot120 Lurker Find all posts View Profile Close BigFoot120]

'05 KZJ120. The trans is the only thing that annoys me, other than that I love it! Bypassing the ECU altogether seems a fairly radical (to me) concept. I was thinking more along the lines of altering the speedo signal to make it shift earlier. I am assuming that these things have a stand alone trans ECU.

A KZJ120. I believe that makes it a 1KZ-TE with a 4spd 340F A/T. Similar to mine but with a 3L diesel.
It's not a stand alone trans ECU. It's all in the engine ECU. I've been going through the wiring diagrams (WDM) to find where the SPD signal is derived. It's a bit confusing.
The speed sensor is connected to the ECU at D14 and D28 in your model. It is probably a pulse input (REF WDM 19 zone 4). The SPD output (actually called SP1 on your model) is on ECU B22 (Ref wire V-R, WDM 14 zone 4). It's shown as an input but I suspect not.
All SPD connections are best shown on the combination meter in WDM 55 zone 5 (wire colour V-R). This WDM shows it fed off to all the other accessories requiring SPD input, including the ECU which is the one of interest for the A/T shift points. This WDM seems to be suggesting the combination meter provides the SPD output. If so, the speed sensor data in the ECU must get to the combination meter is some other mysterious way. I can't see how. This is why I suspect it is an analog output from the ECU based on it's speed sensor pulsed inputs. If so this would prevent you doing anything with it to alter shift points.
If on the other hand the combination meter is the SPD output then the analog SPD input to the ECU would be pretty easy to modify to play with your shift points.
Hence you need to confirm whether ECU B22 is an input or output. I would first put an analog meter on it to ground, go for a drive and confirm that it is an analog signal, where volts are proportional to speed. Then it's a matter of putting a low resistance in series and check the polarity across it. That will tell you if it is input or output. If you get no voltage drop increase the resistance.

Are you with me so far?

Cheers
Bob

[Mule Member Find all posts View Profile Close Mule]

Just like the sentiments of everyone on this thread, I really hate those ECU programmers back in Japan for what they have done to the Auto box on my 09 D4D. The Burma railway would be too good for them, I'd force them into a D4D auto on an around Australia holiday towing a caravan, that would sort them out! Failure to hold lock up when towing, when in a head wind, when you have something on the roof rack, when you put on bigger diameter tyres, when you have a 0.1% up hill gradient just plain sucks. Then there is that other weird thing where in low range you are not getting lock up particularly in the lower gears for crawling and descending steep stuff. How about the way it wants to hold second gear to the death rather than dropping into first going over sand dunes; you have to manually drop it into first to stop the struggle.

Just about everything that could go wrong did go wrong with my old 1999 Discovery 2 but at least they got that ZF 4 speed programming right, the box was pure delight to use. Holding gears when appropriate, staying locked appropriately, shifting beautifully and lock up in all four gears in low range. So, is it not possible to have the Prado auto gear box ECU reprogrammed or drop in a new chip? or exchange.

The concern regarding the clutch packs in my opinion is real, if the lock up does not come off with gear shifting, so if any of the above brilliant rewiring or digital suggestions can do that and you make a batch, I will put my hand up to purchase and install one. Thanks for those of you putting in the hard yards.

[chardo Junior Member Find all posts View Profile Close chardo]

MRW82
Hi Mark, Looks like you now have 2 of us for a start if you want to make a few of your locker kits. Have you had any thoughts on it yet???? Be good pocket money.

BigFoot120
Hi Bob, I haven't said anything much as Wow, you take my breath away with all the things you and the boys are getting into. Keep it up Im watching even though I don't understand it all. Have a good one. Cheers Bill.

[smally Junior Member Find all posts View Profile Close smally]

A KZJ120. I believe that makes it a 1KZ-TE with a 4spd 340F A/T. Similar to mine but with a 3L diesel.
It's not a stand alone trans ECU. It's all in the engine ECU. I've been going through the wiring diagrams (WDM) to find where the SPD signal is derived. It's a bit confusing.
The speed sensor is connected to the ECU at D14 and D28 in your model. It is probably a pulse input (REF WDM 19 zone 4). The SPD output (actually called SP1 on your model) is on ECU B22 (Ref wire V-R, WDM 14 zone 4). It's shown as an input but I suspect not.
All SPD connections are best shown on the combination meter in WDM 55 zone 5 (wire colour V-R). This WDM shows it fed off to all the other accessories requiring SPD input, including the ECU which is the one of interest for the A/T shift points. This WDM seems to be suggesting the combination meter provides the SPD output. If so, the speed sensor data in the ECU must get to the combination meter is some other mysterious way. I can't see how. This is why I suspect it is an analog output from the ECU based on it's speed sensor pulsed inputs. If so this would prevent you doing anything with it to alter shift points.
If on the other hand the combination meter is the SPD output then the analog SPD input to the ECU would be pretty easy to modify to play with your shift points.
Hence you need to confirm whether ECU B22 is an input or output. I would first put an analog meter on it to ground, go for a drive and confirm that it is an analog signal, where volts are proportional to speed. Then it's a matter of putting a low resistance in series and check the polarity across it. That will tell you if it is input or output. If you get no voltage drop increase the resistance.

Are you with me so far?

Cheers
Bob

Yeah, I'm following what you are saying & I appreciate your efforts in nutting it out. Just to clarify the last point about checking ECU B22, how much resistance would you recommend I start with? I'm guessing a resistor from Dick Smiths would be the go, or could I get away with a small globe? As far as the polarity indicating input or output, I assume if it's an input then the ECU side of the resistor would be the negative, based on electron flow?

[BigFoot120 Lurker Find all posts View Profile Close BigFoot120]

Yeah, I'm following what you are saying & I appreciate your efforts in nutting it out. Just to clarify the last point about checking ECU B22, how much resistance would you recommend I start with? I'm guessing a resistor from Dick Smiths would be the go, or could I get away with a small globe? As far as the polarity indicating input or output, I assume if it's an input then the ECU side of the resistor would be the negative, based on electron flow?

Smally: Yes your right. The signal on B22 should be positive with respect to ground. If you put a 10 ohm resistor in series, the most positive end will be the source. In other words, with your meter across the resistor, the positive end will be the source. If you don't get an indication increase the resistor to 100 Ohm.

On thinking about this further, I think we may be chasing the wrong thing with speed. RPM and load may be more important parameters in determining shift points; particularly in the situation you were in when overtaking. Unfortunately both of those parameters are generated within the ECU, so your not going to be able to fiddle them to change anything.

The best way may still be to bypass the ECU completely and do it all in an "add-on" A/T ECU, which would drive both shift solenoids and the TCC solenoid. The shift points would be based on RPM (TACH), Speed and load, all available from the ECU. All pretty easy to do in a small 18 pin PIC micro-controller. It would end up being about the size of two matchboxes like my auto release TCC locker. Then it would be very user programmable, via a PicKit3 programmer (about $60 worth) and a free IDE from MicroChip. The only risks I can see is that the ECU may spit fault codes in some situations, especially later/smarter models.

[BigFoot120 Lurker Find all posts View Profile Close BigFoot120]

The MATCU (Manual Auto Transmission Control Unit)

Hi all

With everyone complaining about TCCs not locking when desired and shift point issues, the best solution for all us Prado owners may be manual control of the A/T, like many modern cars have these days.
I'm not sure about the 5 speed, as I don't have one to fiddle with, but I know it would be a fairly easy mod in the 4 speed.
The control panel would consist of a power "ON-OFF" switch, a centre OFF/ON/ON momentary toggle switch (for shift Up/Down) and 5 LEDS. One LED for each gear and one annunciating TCC state.
The control unit would need to break the connection between the ECU and A/T solenoids (S1, S2 & S3) and take control of them just as done for the TCC locker solenoid (S3) in all the designs in this thread.
It would need Tach and Spd analog inputs and a Drive selection discrete (D) from the ECU as well as 12VDC (Ign) and ground.
The system would be armed by selecting "D"rive, then activated by selecting "ON" on it's control panel. The current gear and TCC state would be retained.
Pushing the momentary toggle switch UP shifts up 1 gear and DOWN shifts down one.
The gears would include the TCC lock and unlock states, so the four speed would have 8 gear selections. If you wanted to go from 3rd locked to 4th locked you would simply push the momentary toggle switch UP twice. This makes it very easy to ensure the TCC is unlocked during gear changes.
The SPD input is required to protect against selecting a gear too low for the speed.
The Tach input is required to disconnect the TCC when RPM falls below idle, thus ensuring it doesn't stall the engine and that it stays locked during engine braking applications.

"Switch OFF"
If you want to go back to normal A/T just switch it "OFF". The design would need to ensure that the TCC is unlocked and that the current gear selected by the A/T was engaged before returning control to the ECU. Otherwise an undesirable "TCC locked" gear change could occur.

Now building the control unit is the fun part.

It could be simple electro mechanical (relay logic) but that wouldn't have the features provided by the SPD and TACH inputs and it would be difficult to cover the "switch off" requirements mentioned above.

It could also be simple analog circuitry, discrete transistor switching and relays, but it would be quite complex and difficult to provide optimized Spd and Tach thresholds for different models (petrol/diesel)

I know some of you guys will hate this, but the simplest solution, by far, is to use one of my favorite micro-controllers. It would need three 2 Amp miniature two pole relays, three discrete transistors to switch their coils, voltage reg and some simple input scaling and protection circuitry and that's about it. This could also provide lots of other smart features like auto changing up when at max engine RPM.

Any suggestions anyone?
Cheers
Bob

[Mule Member Find all posts View Profile Close Mule]

I don't have what it takes to offer suggestions Bob but I do like where you are going!

[BigFoot120 Lurker Find all posts View Profile Close BigFoot120]

I don't have what it takes to offer suggestions Bob but I do like where you are going!

Ha ha, Thanks Mule. I'll start a new thread when it's all finished. This is as good a place as any for the interim.
I have a few bits on order from O/S for it. I expect they will arrive in around a month.
In the mean time I've got the display panel and wireless control paddles done and installed and started writing the software requirements.
I'm quite excited by this little project. I think it will work well, but there is a long way to go and probably some challenges.

I've created a new Dropbox folder for the docs if anyone is interested in progress. Here it is:
https://www.dropbox.com/sh/s97o8wisy...oT8OSzFDa?dl=0

Cheers
Bob

[smally Junior Member Find all posts View Profile Close smally]

Be nice (and therefore expensive no doubt) to have the manual mode incorporated in the shifter, much like a BA Falcon & others where you flick the lever across into manual mode and shift up & down sequentially.

[BigFoot120 Lurker Find all posts View Profile Close BigFoot120]

Be nice (and therefore expensive no doubt) to have the manual mode incorporated in the shifter, much like a BA Falcon & others where you flick the lever across into manual mode and shift up & down sequentially.

Mine won't be expensive, however there will be a lot of time involved in developing the software but I have that at the moment. I'm somewhat grounded from going bush for a few months yet.

I'll be building mine on vero-board using soldered wire wrap wire and thru hole components as I usually do for prototypes.
I'll try to show vero-board track cut detail so it can be copied if anyone is keen enough. A PCB would be nicer of course.

I've already posted the circuits and currently working on the software requirements, which I am posting as I go, in case anyone has some suggestions in terms of functionality. For example, I've recently included a TCC locker function. If anyone can think of any other nice features I would appreciate hearing from them.
I'll post the software and how to program it as well, once I'm happy with it all.

The circuits are looking a little complex but there's nothing expensive there.
The RS232 port hardware could be omitted as it's only to assist me with software development.
The PicKit3 programmers are around $50 on eBay. The processors are under $10. The only other expensive part is the 4 channel wireless receiver and sender for the home made poly-carbonate paddles. Again eBay is the source. $13.47 gets you this: http://www.ebay.com.au/itm/361154396...84.m1439.l2648

Mine will cost around $100 by the time I'm done.
Still a few more parts coming from O/S before I can get into the PCB assembly.

Once again this is the link to documents: https://www.dropbox.com/sh/s97o8wisy...oT8OSzFDa?dl=0

There are a lot to go yet and probably many revisions to those already done.

Cheers all
Bob

[BigFoot120 Lurker Find all posts View Profile Close BigFoot120]

Got all my bits for the MATCU from O/S now so no excuses. I've posted a few more pics of the paddle switches, wireless receiver and the PCB layout.
Should be writing code in about a week.

Cheers All
Bob

[smally Junior Member Find all posts View Profile Close smally]

Sounds good! I really need to do something, had a minor 'brown moment' today on the highway when passing a B double. On the wrong side of the road at 100kph with the trans kicked down into 3rd & not accelerating is no fun. Hard to back off to get it to upshift when there is a car closing on you at 200kph!!

[chardo Junior Member Find all posts View Profile Close chardo]

MRW82
Hi Mark, hi all, I was wondering if you would be able to do an update of your project as on "page 8" with the extra resistors and all. Have you done anymore testing since last letter. Main question, have you thought of making a few up for pocket money???? Im sure there are a few watching and waiting. All the best, cheers Bill.

[Rusty62 Advanced Member Find all posts View Profile Close Rusty62]

Have been watching this thread with interest. So much so on the weekend measured voltages and current for the lock up function. Lucky for me my son is an electrical engineer.

So far all the wiring diagrams from suppliers have been wrong or not for my VX 120 series. We found the wires on the gearbox and traced them back to the ecu. From there we measured voltage - anywhere from 1/2 lock @ 3.048 volts 0.564 amps and through to full lock at 6.78 volts 1.016 amps.
Now to design the relay to make it work. Something about a DPDT latching relay and a 25 watt load resister powered from an external 12 v source. Momentary push to lock and brake light power to unlock.

If it works might do up a kit and sell them.

Rusty.

[chardo Junior Member Find all posts View Profile Close chardo]

Rusty62
Hi Rusty, I have been watching this area for quite a while too. Jamie set up a system like what you are onto with the "mom button" and Mark set up with just a switch. I am looking at just a switch so I am able to use the brake pedal if needed on a long downhill run with the caravan in tow, while still using the lock up as brake with the engine. I am waiting to see what Mark will do with his when he gets everything spot on and if he will make a few kits as the price to buy one is just unreal. Something like $475 + postage. If Mark updates his system on site I may have a go at building one for my beast. Anyway good to see someone else at it too. Take care , Cheers Bill.