Playing around with the 2.7 software (ECU and TCU)

[Adrian D]

The advantage of the newer versions is that they might have a working checksum calculation, as opposed to the v13 which I have.

MPPS, WinOLS free (for viewing / comparison), HxD (for editing), ECM Titanium for checksum.

I usually make the changes in WinOLS since values are shown in base10, copy the changes in the new binary file in HxD and then load the new binary in WinOLS to compare. If all is well, I calculate checksum and flash


I'll need to confirm the cooling maps by getting the fan to trigger at lower temperatures.
Normally, a quicker ramp-up past 100*C can be achieved by changing the 106*C Y-axis point to 102-103*C.

[Adrian D]

Originally Posted by RTB

As a side not here. AdrianD is without doubt the man to ask the detailed questions to. I am just starting out with car ECU tuning, but learning fast. I do have a strong history of writing and modifying machine code for industrial equipment, but never a car so far.

If you just want to view your tune you need the MPPSV13 and its software to get the maps out of your car.

Then there is a free version of a program called WinOLS. This allows you to view your maps, but you do need to set up the maps using the addresses provided earlier, or merge someone else's tune that has already got the maps defined.

From that point is where you want to make some changes.

So there are several options here. From programs called "hex editors" to proper packages. The paid version of WinOLS will allow you to change and save your tune. I am cheap, so trying to do it for as near to free as possible. I have started using a free version of a program called VAG EDC15P+ Suite. It is not specifically designed for our cars, but does allow maps to be viewed, changed, and saved. It is slightly harder to set up than WinOLS, but I haven't actually played with it too much yet to see if it is just me.

Once you have saved your your changes you need to fix the "checksum". The most common method for this can't be discussed openly on forums it would seem, so I won't.

This is why I am looking for another free way to calculate the checksum. I am not putting that much effort into this right now as I still need to wait 2 weeks for my MPPS to arrive. It will start becoming a bigger priority soon, but trying to get my map builder working as I think it will help get changes done more efficiently.

AdrianD. Please make sure you correct me with anything I say that could be misleading or wrong. I want to share everything I learn, but not lead anyone down the garden path.

Can't complain and having extra tools to do this is definitely why getting more brains in this is a good idea

[JeanLuke]

Originally Posted by RTB

I did wonder about the V21. Let us know how you go with it once you get your hands on it.

It's not due until early May, so don't hold your breath waiting. AliExpress is cheap, but it isn't fast.

Sent from my moto g( plus using Tapatalk

[JeanLuke]

The cooling map is my main interest. I'm running HC refrigerant rather than HFC, so I should adjust the AC trigger to a lower pressure.

Sent from my moto g( plus using Tapatalk

[RTB]

Originally Posted by Adrian D

Can't complain and having extra tools to do this is definitely why getting more brains in this is a good idea

Hey AdrianD. I've been looking at the TCU maps. Noticed there were 3 different gear change schedules for each gear set. Would you know what they are?

Is it high range, low range, and cold temp change maps?

[Adrian D]

Originally Posted by RTB

Hey AdrianD. I've been looking at the TCU maps. Noticed there were 3 different gear change schedules for each gear set. Would you know what they are?

Is it high range, low range, and cold temp change maps?

Good question.

One of them is for sure low range, I haven't investigated that much into it.

A clear test would be to change one map to upshift at 3000rpm on all load conditions.

Low-range ignores first gear completely, so I suspect C (comfort) is low-range. S or M are high range.

For cold starts the Cold temp offset is used, description is included in the map.

[RTB]

I thought about just sending this question directly to you AdrianD, but I guess this thread is designed to allow the community to discuss and explore what might be possible. We might as well examine the entire range of potential mods, not just the more fuel, more air that many tunes focus on.

So, it would appear we have a drivers wish map for high range, a different one for low range.

We also have different shift schedules available for high range and low range.

The transfer case switch appears to be connected to the ECU, not TCU, therefore the low range signal must be sent to the TCU via comms.

My goal with tuning is to improve relaxed drivability. So, I am aiming for increased bottom end torque, lower shift schedule, earlier TC lock. All great stuff for lightly loaded conditions.

Problem is when it comes to towing. Sure I could just try and fine tune the DW map with regards to throttle input, but I think that would result in a less smooth experience.

Now for all those people reading, this is just a theory question for now.Trying to put some thought into what might be possible. Food for thought.

What do you think would be the result of the list below?

Take the wires from the transfer case switch up to a manual switch on the dash.
Adjust the TCU high range shift schedule to match my relaxed lower reving driving style.
Adjust the ECU high range DW map to provide lower boost at lower throttles for economy AFR, but then increased boost/IQ at lower rpm and mid throttle for the low down torque when needed.
Adjust the TCU low range shift schedule to up the RPM a bit and provide a more responsive engine.
Adjust the ECU low range DW map to provide more boost at lighter throttles to keep the exhaust temperatures down.
Adjust the TCU low range ratio to 1.

As far as I can tell, the transfer case is an entirely mechanical device and doesn't care about fancy programing.

So with the transfer case in high range. The switch on the dash could be used to change between the relaxed map, and towing map in both the ECU and TCU.

Problem would come when actually selecting low range. If I am looking at this correctly, this would result in extremely low rpm gear changes as the output shaft of the transmission is expecting to see a 1/1 ratio in it, but instead is 2.72/1.

Obviously this is a really bad situation. Now this bit is where we are all different, but I rarely, if ever, go off-road anymore. It would mean that on the extremely rare occasions that I hit low range, I would need to manually select each gear to bring the rpm back to normal.

For me, and my driving style, I think I could handle this. The benefit of having a normal mode, and towing mode in the ECU and TCU tune would far outweigh the hassle caused to the actual low range driving.

Oh, and I guess heading off for a weekend of off-road driving would be a planned thing for me, so I could just whack the original TCU tune in for that time if really required.

What do you think? Potential area to explore, or crazy idea that will result in a fireball parked by the side of the road?