Torque Convertor lock up instal

[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

[Mule]

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

[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

[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.

[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?

[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.

[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.

[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

[smally]

Smally. Your right! I was thinking "old world" with my thoughts on shift points. Yes the ECU is where the shift points are determined. It wouldn't be too difficult to do your own thing and completely bypass the ECU control in the 4 speed at least. I don't think it would spit fault codes. It may be different story on the later models though. I think I would use a purely digital approach using a PIC microcontroller with A to D capability so I could take in Tacho and Speed analog inputs as well as the pressure control solenoid voltage which gives load info. Then it would be a simple mater of driving the shift solenoids. Thinking out loud here. There are other issues in the 4 speed, and probably others, in that some of the gear selections are mechanical. Park and reverse for example. However you do have those signals as discretes to the ECU so it wouldn't be too bad.

I'm intrigued that yours is a bit late upshifting. My 4 speed is opposite to that. It's a bit late downshifting when slowing down under light loads. What model Prado are you running?

Cheers
Rob

'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.

[BigFoot120]

Crickey Bob, I've read all your instructions, and may I say just how complex and proffesional they are. It must be your area of expertise as a layman as myself would have buckley's of coming up with all that. Well done!
My basic, self made lock-up system is nothing to all that, but I must say it works a treat. I understand yours and anyone elses concerns about the trans shifting gears whilst the TC is locked. I am just being a guinea pig and seeing just how long it will last. So far (18,000km approx) no sign of a problem. If a problem rears its ugly head, I will post it here for sure.

Well done again Bob,

Cheers, jamie

Thanks Jamie. I would hate to count the number of years I have been in this game. I still get a kick out of designing weird things, even though it was my job. My car and boat are full of them.

There's nothing wrong with your electromagnetical approach. There always easy to troubleshoot when things go wrong.

If you stick to using your full time locker on trips, when you are mostly at cruise, there will be minimal locked mode changes happening, so life of those selection clutches shouldn't be impacted significantly.

I don't tend to engage my locker around town as I miss the extra acceleration and performance provided by the TC. It's great when towing though. Being able to do something about cruising for miles on end with the TC unlocked is brilliant.
It reminds me of towing a big boat with an old 179 manual EH Holden. Cruising in a head wind, it couldn't hold top gear, so I would cruise for hours at 55mph in second gear. It loved it and economy wasn't too bad. However, I then made the mistake of buying a HQ auto, which of course didn't have a TCC. Towing the same boat was a disaster for the wallet as well as overheating. I had to take the bonnet off just to keep it cool. Forking out all that money on fuel just to heat up a torque converter doesn't seem like a smart thing to be doing.

Cheers
Bob

[BigFoot120]

I hear what you are saying. The shift points are electronically controlled, not worried too much about the internal hydraulics at this stage.
I'd love it to shift earlier if there is a way, the shift logic in these things is awful. Just came back from a 1400km highway trip and I found myself backing off the throttle to get the stupid thing to upshift when over taking. Sounds weird, but no point revving at 3500 and not accelerating when you are on the wrong side of the road!
Any idea on how to make it do this would be appreciated.

Smally. Your right! I was thinking "old world" with my thoughts on shift points. Yes the ECU is where the shift points are determined. It wouldn't be too difficult to do your own thing and completely bypass the ECU control in the 4 speed at least. I don't think it would spit fault codes. It may be different story on the later models though. I think I would use a purely digital approach using a PIC microcontroller with A to D capability so I could take in Tacho and Speed analog inputs as well as the pressure control solenoid voltage which gives load info. Then it would be a simple mater of driving the shift solenoids. Thinking out loud here. There are other issues in the 4 speed, and probably others, in that some of the gear selections are mechanical. Park and reverse for example. However you do have those signals as discretes to the ECU so it wouldn't be too bad.

I'm intrigued that yours is a bit late upshifting. My 4 speed is opposite to that. It's a bit late downshifting when slowing down under light loads. What model Prado are you running?

Cheers
Rob

[smally]

I'm probably not the one to address this. I'm more into the electronics side of things, though I have overhauled A/Ts for my own purposes. Not much experience with the hydraulic controls though. I would like to reduce the speed at which the TCC engages. 80k in 4th and 70k in 3rd is too high. If it were possible to reduce it that would be the best solution.

I hear what you are saying. The shift points are electronically controlled, not worried too much about the internal hydraulics at this stage.
I'd love it to shift earlier if there is a way, the shift logic in these things is awful. Just came back from a 1400km highway trip and I found myself backing off the throttle to get the stupid thing to upshift when over taking. Sounds weird, but no point revving at 3500 and not accelerating when you are on the wrong side of the road!
Any idea on how to make it do this would be appreciated.

[Davis Dieso]

Now that the silly season is over I finally got around to installing my auto release TCC locker and it works as expected however I do have some issues with the concept with it's application to 4spd petrol versions at least. There is a tendency to struggle when the additional gears provided by the TC for 3rd and 4th are removed. This may not be such an issue for diesels with their broader torque curves.

Here's the link to the documents. I've updated the description doc to add the test drive results and added a couple of installation pics.

https://www.dropbox.com/sh/eq3pu6e7f...OomAu6lra?dl=0

Cheers
Bob

Crickey Bob, I've read all your instructions, and may I say just how complex and proffesional they are. It must be your area of expertise as a layman as myself would have buckley's of coming up with all that. Well done!
My basic, self made lock-up system is nothing to all that, but I must say it works a treat. I understand yours and anyone elses concerns about the trans shifting gears whilst the TC is locked. I am just being a guinea pig and seeing just how long it will last. So far (18,000km approx) no sign of a problem. If a problem rears its ugly head, I will post it here for sure.

Well done again Bob,

Cheers, jamie

[MRW82]

G'day bill, I haven't really got anything more to report as I haven't done any more towing, I have played around without towing and it works fine but is unnecessary without any load as the auto is pretty smart anyway.

[chardo]

MRW82
Hi Mark, Happy New Year, Have you put a few more Kms on the testing, and how is it going??? I think there are a few waiting for more news. Cheers Bill

Happy New Year All, Hope 2015 is a good one for everyone. Cheers Bill.