Auto > Manual conversion TCL / ASC experimentation

[Piers1989]

Ok, to kick this off let me initially say I have searched a lot of info and I know the general consensus is that if you convert to manual you lose TCL/ASC as they are partly controlled by the autobox ECU.

That said I have been pouring over information to try to figure out WHY this is the case.

With that in mind I have been looking at the pinouts for the relevant ECUs:
For reference I have a 7202 ECU in my car from a manual, and it is working fine with my cars TCL and ASC system - and I'm about to be converted to manual.

AutoBox ECU
http://www.clubvr4.com/forum/showthr...ght=ecu+pinout
ABS/TCL/ASC/AYC ECU
http://www.clubvr4.com/forum/showthr...ght=ecu+pinout
Main Engine ECU
http://www.clubvr4.com/forum/showthr...ghlight=pinout

Thanks to everyone who contributed towards these as they are amazing information

My initial questions are, after converting to manual:

1. After bypassing the start inhibitor, can we not leave the Auto ECU connected? If this is done (other than errors for lack of gearbox connected), does anyone know the result?
2. I note that Pin 21 on the A/T ECU is "Torque Decrease signal to ECU(Eng) from TCL" - this I assume is actually the gearbox relaying a "cut throttle" command to the engine ECU from the ABS/TCL/ASC/AYC ECU. This is obviously an important part of the process - but if the ABS/TCL/ASC/AYC ECU has 2 direct links to the Engine ECU, why would it be this way?
3. Pin 45 is noted as TPS and APS, but as only one wire, I assume it does not connect to both? Does anyone know specifically what this is connected to? I believe the Engine ECU takes the input from the TPS only and the APS is therefore likely to only be used by the gearbox to determine what gear it should be in based on pedal input?
4. Pin 53 and 54 connect to the AutoBox ECU for unspecified communication. It would logically only make sense for it to communicate relevant data (I would assume). Does anyone know exactly what is reported? I would imagine just Output Speed, maybe input speed, and any error codes for the ABS/TCL/ASC/AYC ECU to pass on to the engine ECU / Dash.
5. Overall, looking at the AutoBox connectors, it doesn't look like the ECU really has that much to go on. Perhaps it would be feasible to use an Arduino or similar to SIMULATE the gearbox working based on RPM or similar such that it doesn't know there is a lack of gearbox? For example as soon as car is turned on go into NEUTRAL (will have to test if ASC works in neutral) or if that doesn't work, go into Manual mode 1st gear, and make the arduino fake reasonable input and output speeds based solely on 1st gear and the engine RPM.

For those of you with the technical background it would be really cool if we could figure this out! I'd be happy to share everything with the club including the Sketch and Arduino pinout if it was needed / worked!

[adaxo]

Very interesting thread, can answer question no 1, you have to remove auto box ecu to make a way for manual linkage. Remember as i come across this on my conversion and it take a bit of thinking to figure out why this @#$&€$# linkage wont fit, straight after removing auto ecu, they jump in they place and fit like a glove.

[Piers1989]

Very interesting thread, can answer question no 1, you have to remove auto box ecu to make a way for manual linkage. Remember as i come across this on my conversion and it take a bit of thinking to figure out why this @#$&€$# linkage wont fit, straight after removing auto ecu, they jump in they place and fit like a glove.

That's something to note at least. I'm sure that can be overcome in one way or another!

[Grid]

Also take into account that TCL/ASC were optional and I think even removed on late facelifts. I have a late FL auto and no TCL/ASC. To really make sense of what is happening between the ECUs you'd have to start datalogging (storage oscilloscope or Logic 8/16) the signals between the various ECUs. I doubt progress can be made by just reattaching wires.

I note that Pin 21 on the A/T ECU is "Torque Decrease signal to ECU(Eng) from TCL" - this I assume is actually the gearbox relaying a "cut throttle" command to the engine ECU from the ABS/TCL/ASC/AYC ECU. This is obviously an important part of the process - but if the ABS/TCL/ASC/AYC ECU has 2 direct links to the Engine ECU, why would it be this way?

The autobox is protecting itself from damage when operating pressures are getting exceeded.

[Piers1989]

Also take into account that TCL/ASC were optional and I think even removed on late facelifts. I have a late FL auto and no TCL/ASC. To really make sense of what is happening between the ECUs you'd have to start datalogging (storage oscilloscope or Logic 8/16) the signals between the various ECUs. I doubt progress can be made by just reattaching wires.


The autobox is protecting itself from damage when operating pressures are getting exceeded.

Oh I agree Grid.
I'm pondering the best way to get this information, part of the reason for posting was to check someone hadn't already done it.

I doubt it will be as easy as attaching the ECU and faking the car being in neutral, but it's worth trying!
Otherwise most of the data the ECU processes seems to be analogue (the solenoids and inhibitor switches). Even things like the speed shouldn't be too hard to reproduce.
I would imagine it will be very hard to decipher whats going between the ECUs exactly without understanding the packet structure - but just giving the ECU fake readings such that it doesn't throw errors in the first place may not be so hard, then as long as it relays normal signals between the ECUs, happy days.

[Grid]

The signals between the ECUs would be analogue (single wire), PWM (single wire) or if they are digital they would be a type of local OBD bus (pair of wires). It's not unheard of that cars have more than one OBD bus/CAN, usually just one is exposed to the outside world and the other ones are internal for critical communication. Some insight into this could be gleaned by opening up the enclosures of the ECUs and tracing the paths of the pins you suspect that handle the communication. They would either terminate at the CPU or at some converter chip.

That for the ambitious solution ;-) A more down to earth approach could indeed be to leave the autobox ECU in place and just feed it with whatever sensor data (faked or real) that it needs to start communication with the other ECUs.

[elnevio]

As far as I am aware: all PFL autos had TCL/ASC; all facelift autos did not have TCL/ASC - although it was an optional extra, and very very rarely opted for! There must be a few out there, but I don't recall seeing a facelift auto with it!

[Piers1989]

To keep this updated - my cars been dropped off for conversion starting today

Before dropping it off I also tested (for science!) that the ASC would work in Neutral.
I put the car in neutral at about 40mph on a big empty roundabout and yanked the wheel. I can confirm ASC DOES function when the car is in Neutral.
This may make it easier to keep the ECU happy.

[BCX]

My initial questions are, after converting to manual:

1. After bypassing the start inhibitor, can we not leave the Auto ECU connected? If this is done (other than errors for lack of gearbox connected), does anyone know the result?
2. I note that Pin 21 on the A/T ECU is "Torque Decrease signal to ECU(Eng) from TCL" - this I assume is actually the gearbox relaying a "cut throttle" command to the engine ECU from the ABS/TCL/ASC/AYC ECU. This is obviously an important part of the process - but if the ABS/TCL/ASC/AYC ECU has 2 direct links to the Engine ECU, why would it be this way?
3. Pin 45 is noted as TPS and APS, but as only one wire, I assume it does not connect to both? Does anyone know specifically what this is connected to? I believe the Engine ECU takes the input from the TPS only and the APS is therefore likely to only be used by the gearbox to determine what gear it should be in based on pedal input?
4. Pin 53 and 54 connect to the AutoBox ECU for unspecified communication. It would logically only make sense for it to communicate relevant data (I would assume). Does anyone know exactly what is reported? I would imagine just Output Speed, maybe input speed, and any error codes for the ABS/TCL/ASC/AYC ECU to pass on to the engine ECU / Dash.
5. Overall, looking at the AutoBox connectors, it doesn't look like the ECU really has that much to go on. Perhaps it would be feasible to use an Arduino or similar to SIMULATE the gearbox working based on RPM or similar such that it doesn't know there is a lack of gearbox? For example as soon as car is turned on go into NEUTRAL (will have to test if ASC works in neutral) or if that doesn't work, go into Manual mode 1st gear, and make the arduino fake reasonable input and output speeds based solely on 1st gear and the engine RPM.

My responses to these points:
1. I'd remove the TCU. The ECU doesn't need it to run. Do you know what ROM your ECU is running? there is potential to either modify yours to turn off unneeded functions, or just flash a manual rom.

2. I personally have a Manual VR4... but as someone who does development for a VR4, Evo and Magna... After playing with an automatic Magna use one of these as a signal to retard timing. there is a 3d map within the ECU that controls how much to retard the timing, thus reduces the amount of torque. This signal is generated by the TCL system

3. You'll want the TPS to be the input to the ECU as this is the one that is joined to the butterfly. The APS exists for the TCL (so it knows how much you're putting your foot down compared with the TPS which is the actual throttle postition). Automatics without TCL only have TPS.

4. The H8 processor does have 3 uarts in total... 1 is used for MUT via the OBD2 connector... but i cant confirm that the others do if they are even utilised. I do believe that these signals might be simple digital inputs (0 =off, 1 = on). My fix would be to flash a manual ROM on. If you're still after the TCL/ECU ability to retard the timing, you can switch this function on/off

5. Just remove the TCU. It's the easier way. Realistically, you'd need to capture all the relevant signals with an oscilloscope on a dyno, then design hardware and write software to emulate something. Arduino uno only has limited timer and pwm outputs. You'd need something with more grunt.

Cheers,
Bill

[Piers1989]

Sorry for the delay in updating this, if you've seen my other threads you know there's been issues with the clutch / box causing the car to have been off the road a good while!

Anyway, to update.

• The car was converted to manual and the TCU left connected
• I was already running a 7202 from a manual car, that was previously working fine with TCL. No flashing light and was functioning correctly.
• After the conversion, all the lights on the gear indicator do not illuminate (R does if I turn the reverse switch on)
• TCL light does not flash, and can be turned on and off normally. Does not seem to operate correctly. Skid light illuminates under high power or heavy cornering. Car does not cut power but does "feel" like something is happening. Maybe its breaking on some wheels?
• ASC (the one I want to keep!) SEEMS to be non functional, haven't gotten a skiddy car to come on with TCL turned off.

I was trying to do some diagnostics with EvoScan to see what the TCU was reading from the transmission sensors. I noted at this point that when it usually flashes the "N" in the gear indicator to show fault codes, it still did not illuminate.
My EvoScan does not seem able to start to open the ECU due to an error

Conversion from String "&HTCU" to type "integer" is not valid

This is before it tries to connect to the ECU so I think its software related.
I had a goggle but couldn't find any results for how to fix this. Any ideas?

I was able to do some datalogging for the AYC ecu giving lots of information, all of which I believe looks normal. I attempted ABS too but as some reported in another thread, the ABS pump goes mad during diagnostics meaning the car is undrivable.

[Piers1989]

Little bit more of an update.

I haven't gotten round to looking further at the TCU, but now the new clutch is bedded in and I've got a decent map running around 1bar of boost I've been having some fun in the car on my journeys to Cumbria and back.
I've always been driving with TCL off as it is intervening with acceleration.

Their's a lot of grit on the faster roads around Shields and I was able to get some nice 4 wheel drift action on - and I noticed when I turned the wheel to counter it the ASC kicked in!
Tested this a few times on some larger roundabout exits and definatley some intervention and ASC light.

Need to devise a way of determining if it is working "as it should", but at a glance, it seems all may actually be well with TCL just turned off.