Hacking your TCU with xHP Flashtool

[xQx]

So, in the next couple of days xHP is due to release maps for our cars to replicate and improve on the benefits we’ve had in the past by running the Alpina flash (faster shift times, changed shiftpoints and display the gear in S/D mode).

But xHP and the maps aren’t cheap – it’s $120USD for the base flash license, then up to $90USD for the maps.

So if you’re just looking to fix a couple of specific annoyances in the coding, you might be able to save yourself $89 by fixing it yourself. (You still need to buy the base license for $119 USD)

Now, a quick warning: BMW probably had good reason to put the shiftpoints where they are. Forcing your Auto Trans to hang in gear at excessively low and high revs is probably going to shorten the life of your gearbox, it may even cause rapid failure. If you are silly enough to program the gearbox to shift up to third at a lower speed than it’s programmed to shift down to second – Tuner Pro and xHP are probably going to let you. Don’t ask me what it does, but I doubt it’d be good.

But the good news, if you want to eliminate the auto-upshift on redline and auto-downshift near idle in manual mode, modify the upshift in drive mode so it hangs in gear longer, or just turn on the gear display in S/D mode on your gearbox, it’s a walk in the park. If you’ve flashed with MHD and can use Microsoft Excel, you’ll be fine.

So, first, download xHP onto your Android tablet, turn your car to on, JB 4 to map 0 and plug it in using your ODBII cable. (All the same as if you’re doing a MHD flash). Load up xHPFlashtool and make sure it connects and says your car is compatible.

Now, Put the android in aircraft mode, Pull your LPFP fuse, put the car on a charger, close all your doors and do the TCU backup. This will take about 40 minutes and tell you when it’s complete.

Now, pay the $119USD base flasher license fee, and load the xHP initial flash onto your TCU, which will take about 30 minutes. All should be success up to this point.

Take your car for a short drive to make sure everything is rosy before you start and come back and fire up your laptop.
Download tunerpro (free) from: http://www.tunerpro.net/downloadApp.htm
And the xHP xdf file from: http://www.xhpflashtool.com/

Now, using file manager on your Android tablet, find the xhp_backup_tcu_[bunch_of_characters].bak, xhp_backup_coding_[bunch_of_characters].bak and xhp.state files in the backups directory on xHP and copy these to your PC.
All up they’re less than 2MB, so you can email them if easiest. But get them on your PC and store a copy somewhere safe.

Now, open tunerPro, click XDF in the menu, then “select XDF”, unzip and find the xdf file you downloaded from xhpflashtool.com. Save a copy of your xhp_backup_tcu_[bunch_of_characters].bak as my_tcu_tune.bin (or something similar), then go to File, Open Bin and find your my_tune.bin file to open the stock TCU map in TunerPro.

Now the fun part.

To turn on D/S gear display in the dash, find the “Switch for Gear Display in Dash” Scalar, and change it from blank, to 2.

To change your automatic gear-change shiftpoints, you’d be modifying the “shiftmap” tables. Hover over each of the tables to get a description of what they’re used for, but start with changing the Steptronic table (since it’s easy).
Open the Steptronic 1 table, and you should have 10 columns, and about 13 rows.

From left to right, the columns are the output shaft RPM (speed) at which the car changes gear. From top to bottom, the rows are the load/throttle position. The top row is idle, the bottom row is 110% throttle (kickdown) and the second-bottom row is 100% WOT. In the steptronic tables, you’ll notice the values in each row are all the same (except the last row which is when you’ve mashed the throttle into the kickdown button) – meaning the automatic upshift & downshift happen at a set speed regardless of your throttle input.

By way of comparison if you look at any of the Drive or Sport shiftmaps, you’ll see the numbers generally increasing as the rows go down – meaning it will kick down a gear earlier and change up a gear later the more you mash the throttle.

Now, the values in the cells are speed, but not mph or kph – it’s output shaft RPM. To convert output shaft RPM to kph or mph, there’s a formula which takes into account your diff ratio and wheel diameter. Since it makes as much sense to me as the Duckworth-Lewis method, I’ll tell you how to get a rough estimation based on your car with minimal mechanical or mathematical knowledge:
1) Take the car for a drive, flick it across to steptronic/manual mode.
2) Find a stretch of highway, and floor it in second gear. Take not of the speed at which your car automatically shifts from second to third gear. (for me this was around 100kph)
3) Now, find an empty stretch of residential road, select third gear and slow down slowly – note the speed at which your car automatically shifts from third to second (for me this was about 23kph).
4) Now, come home back to tuner pro, and divide your speed by the value in the relevant cells where your car is currently programmed to shift up to third or down to second. (For me, this was 23kph / 640rpm = 0.0359375 and 100kph/2750rpm = 0.036363).
5) This means each RPM equates to roughly 0.036kph (in my car).

To find the RPM for a given speed, divide by 0.036; To find speed from RPM, multiply by 0.036.

Again, by way of example you can now see the speeds your car is programmed to auto upshift/auto downshift in steptronic mode.

For me (stock ’08 135i TCU) they were:
Up to second: 1300 rpm = 46 kph
Down to first: [blank] = don’t shift
Up to third: 2750 rpm = 99 kph
Down to second: 640 rpm = 23 kph
Up to fourth: 4350 rpm = 156 kph
Down to third: 896 rpm = 32 kph
Up to fifth: 5950 rpm = 214 kph
Down to fourth: 1184 rpm = 42 kph
Up to sixith: 8200 rpm = 295 kph
Down to fifth: 1600 rpm = 57 kph
*** IMPORTANT NOTE: rpm is OUTPUT SHAFT RPM, not engine RPM. ******

Which matches roughly my experiences from driving.

So, to eliminate automatic downshift and upshift, looking at this table we can either set high/low values that the gearbox will never meet (ie. Downshift at 1rpm, upshift at 9000 rpm), or just blank the values in this table. I’d recommend the first method (and haven’t tested the second).

In my case, I just changed the auto-downshift from third to second from 640rpm (23kph) to 420rpm (15kph) so it still protects the gearbox from me idling at traffic lights in third gear, but is slow enough that it’s below where I’d naturally downshift while driving.
Okay, now open the Steptronic 2 table, and make sure it has all the same values as Steptronic 1 (we don't know which one is used and which one isn't so just program them both the same). hit save on both tables in TunerPro, then go to file, and hit save to save your .bin file.

Get that bin file onto the xHP Custom Tunes folder on your android device, then go back to your car.

Put the car on the charger, set your JB4 to map 0. Plug your ODBII cable in and turn the car to on. Go to tunes in xHP, hit “write custom tune” and select your my_tune.bin file.

Wait five minutes for it to write, then take your car for a drive!
You should instantly see the gear-display on your dash, and now enjoy your custom upshift & downshift.

Once you’ve proven yourself with the steptronic tables, get back to the laptop and start messing with drive and sport modes!

Don’t stress if you do something silly, just start again with the stock bin file we saved earlier.

Good Luck!

EDIT 2: Corrected Prices to USD.

EDIT 2: ALSO NOTE: You can't edit the xHP created maps. All your tuning must be done based on the .bin file you got from your transmission with the initial backup. When you write a xHP map it leaves your TCU read protected. Also, xHP haven't given us access to the tables that enable their rapid-shifting. So, currently you have an either/or choice. Use your own map with regular-speed shifts at your custom shiftpoints, or use one of their OTS maps with the OTS shiftpoints, but with lightning fast shifts.

[iminhell1]

post, to find this later

[Xer0449]

Great post. Very informative.

I wonder if there would be any gains (or if it's possible) for the DCT TCU to be remapped.

[1and1]

Originally Posted by xQx

EDIT: It turns out Google App Store was automatically converting USD to AUD for me, so the costs were in AUD not USD. If anyone with USD as their native currency can tell me what the tune/maps cost I'll update this post again.

Just took a quick look at the 135 maps-

General Flash License - $119.99USD
Stage 1 maps - $49.99
Stage 2 maps - $69.99
Stage 3 maps - $89.99

Hope that helps

[iminhell1]

So I went through the steps laid out here. It works. I don't know if I missed something my first go but there was no backup in my folder (I was waxing my car whilst waiting). Second go round all went well (and now cars fully waxed).

So,
How do I raise the TQ limiter (as described in stage 3)?
- Is it simply the engine TQ curve?


*edit*
Answer is no.
The TQ limiting tables are not publicly available yet.

[Willortiz]

Sub for seeing how this turns out.

[xQx]

Originally Posted by 1and1

Just took a quick look at the 135 maps-

General Flash License - $119.99USD
Stage 1 maps - $49.99
Stage 2 maps - $69.99
Stage 3 maps - $89.99

Hope that helps

Thanks.

I've updated the edit.

Also, have clarified with xhp. There is currently no way of editing their OTS maps, and no way of programming the lighting-fast shifts that they've achieved with the OTS maps.

So this leaves us in a sucky position of having our own choice of shiftpoints, OR lightning-fast shifts. Not both.

[iminhell1]

The "lightning fast shifts" (v3) are no different than Alpina B3. Not one bit.
Vs stock, yes an improvement. But not worth $210.

[xQx]

Originally Posted by iminhell1

The "lightning fast shifts" (v3) are no different than Alpina B3. Not one bit.
Vs stock, yes an improvement. But not worth $210.

Thanks. I've never had Alpina to compare.

It certainly seems the best value for money (potentially even the best option outright) is to get the Alpina flash, then use the method above to change the shiftpoints and fix drive mode in the Alpina.

Leave the off-the-shelf maps on the shelf.

[1and1]

Originally Posted by xQx

It certainly seems the best value for money (potentially even the best option outright) is to get the Alpina flash, then use the method above to change the shiftpoints and fix drive mode in the Alpina.

Leave the off-the-shelf maps on the shelf.

I think that's exactly what I'm going to do. Unless I go autocross again I just don't need the changes to shift logic like higher rpm or gear holding.

[1and1]

Spent some time today working on this project...

Purchased the general flash license
grabbed a backup of 7603527 which is the current "stock" flash for my '09 135
grabbed a backup of 7615835 ("Original" Alpina B3 Flash)

My goals do not include the same downshift from 3rd into 2nd in M mode that the OP has issues with ( xQx ) but I do have massive issues with how slack the Alpina flash is for daily driving in D mode so that's what I changed, and why I worked to grab backup BIN files of both my stock flash and the Alpina flash.

For me, and many others I suspect, it's just the weak Alpina D mode that needs to be twined to the stock flash. The rest of the Alpina flash is fine enough. So for this first pass I just twinned the Shiftmap XE1 and XE2 from the 3527 map over to the Alpina 5835 and flashed the TCU.

I've attached the Excel comparison of these tables to simplify life for ya'll. Attachment file size limitations prevent me from including more

I got a quick drive around and so far I'm finding that D mode is same as stock and M & S modes are same as Alpina- so, yeah, totally happy so far

[Alpha Trion]

Thanks for the write up xQx and info 1and1.

Looking at getting this done after my pure s2 are being installed. I heard the alpina is very docile in D but an animal when in sport mode, this i don't mind.

If you can get the stock settings in D and the aggression when you switch i guess that's perfect!

[Willortiz]

If its the same as the how is it that some car running this flash have been able to pass our limits on the alpine flash? Are they any reputable custom tcu tuners out there

[1and1]

I've updated several other tables in the Shiftmaps category so the list has grown a bit now from just the XE tables. The full list includes-

Uphill A1 - A5 (five tables)
Shiftmap E
Shiftmap Heating Mode 0 - 3 (four tables)
Shiftmap XE 1 & 2 (two tables)

The D mode of the 7615835 ("Original" Alpina B3 Flash) isn't what I'd call "docile", rather more dead. It's instantly to the highest gear it can get and shows clearly that it's not a match to the 135. While I'm sure there are other tables that would improve things if moved from stock 7603527 bin to the alpina bin, for my rather modest needs and goals simply copying over the above tables appears to have provided what I wanted- stock performance in D, alpina performance in S/M- cake and eat it too if you will.

I need to find some time to look at the new tables that have been found and see what other changes would be beneficial. Busy few weeks coming up for me so who knows when I'll get back around to this again tho...