ProECU BMW ECU Unlock Tool


Before being able to flash a rom onto the vehicle, the ECU must first be unlocked.  This process is only required the first time the ECU is programmed from stock. It allows programming of non-OEM ROM files, adds EcuTek licencing information and secures the ECU against reading by third party tools. Unlocking has been improved recently and the overall process is unified across all EcuTek BMW platforms.

The General workflow for unlocking the ECU before tuning is as follows.

Preparing for unlocking

  • Ensure laptop that has sufficient charge to last the unlock process.

  • The car battery will also need to be in good condition

  • Lights, blower, ICE switched OFF!

  • If in any doubt you may want to use a low current battery charger on the car

  • Make sure to leave the key in the car while the process is happening and avoid any additional unnecessary draws on the electrical system.

Use of a battery charger on the vehicle while your computer is plugged into the vehicle for power can cause damage to the computer or the vehicle's ECU.  It's recommended to run the computer off of battery or a power source outside of the vehicle.

Getting Connected

Step 1: Connect EcuTek Interface cable to USB port of PC and OBD port start ProECU


Step 2: Detect or Manually select vehicle or ECU

Clicking on “Detect Vehicle” from the “Tools” pulldown menu, or using the F3 will start automatic detection of the vehicle type.

In some rare cases ProECU may not correctly detect the vehicle, in which case it may be necessary to manually select the vehicle type.

Select the vehicle which matches the target vehicle being unlocked.

Open the Unlock Tool

After the vehicle or ECU is detected or selected, the next step is chosen, the default option is set to "Program Engine ECU" but if connecting to unlock the ECU select "ECU Unlock Tool":  

The Unlock Process

Once the ECU unlock tool has opened, click on "Query ECU" and the ECU will be detected, and its components reported:

Choose the Unlock action

Even ECUs unlocked with other tools such as BM3 or MHD will need to go through the appropriate unlock process prior to programming a tuned ROM file.

Unlock and licence a stock ECU that has not previously been tuned

For many users this will be the appropriate option, and where possible will perform an OBD unlock of the ECU, so it can be further programmed for tuning. If the car is stock, this is the correct option.

Put an EcuTek License into an ECU that is already unlocked and/or tuned

Many older cars will have been tuned using another product such as Bootmod3, MHD or programmed one of many workshop based tools such as CMD, bFlash etc. In this case 95% of all these alternatives use a similar method to allow programming of the full rom. If the car being tuned has previously been OBD unlocked by another tool, ProECU will still need to go through an EcuTek unlock process to program the license information and additional code into the bootloader portion of the ROM.

In some cases an ECU will have been “bench unlocked” with another tool, and ProECU can use the already updated bootloader in the ECU to allow an EcuTek License to be programmed into it.

Upgrade an unlock ECU and licenced ECU to a newer rom version

If the ECU has already been EcuTek unlocked and licensed, but there is an updated version of the BMW software, this option allows updating, even if the bootloader has been updated too.

Flash a stock ROM into the ECU (relock and remove EcuTek license)

If you want to return the ECU to 100% stock condition, choose this option. Do not choose this option if you simply want a stock calibration, it is not required to relock an ECU just to program a stock calibration without RaceROM.

This action will reinstate full OEM programming protection. Any ECU calibration that normally requires a bench unlock will again require bench unlocking for further tuning.

Start Unlock

Click on "Start" and you will be prompted to select a 100% unmodified ROM file. The dialog box will be prefilled with the correct ROM (although some of the name is obscured when the file dialog pops up), you should be able to click on "Open" or just hit the "Enter" key.

If the file is successfully loaded, the progress window will be updated, and the licence status will be reported:

You are now ready to proceed with the unlock process. Click on "Unlock ECU" and progress will begin. This typically takes around 18 minutes, it is normal for the low pressure fuel pump to run.

Conclude unlocking

When the unlock process is complete the ECU will be reset and DTCs cleared. Cycle the ignition by turning off for a few seconds and then back on to restart all the other modules on the car.

If the ECU is unresponsive, or the car will not start, make sure to cleanly return the ECU to normal operation by clicking on the “Exit Programming Mode” button.

ECU Unlock Troubleshooting

  • In some cases, it may be necessary to do a second vehicle-wide clear DTC operation after the ECU unlock process and/or an additional ignition power cycle.

  • If for whatever reason unlocking is interrupted or fails, it should be possible to restart the process without issue.

  • After an unlock failure, it is possible the ECU is partly blank and will not communicate using normal OBD commands, thus the vehicle cannot be detected. If you close and re-open ProECU for whatever reason (eg laptop ran out of battery) you will need to manually select the vehicle, do not rely on autodetect.

  • If restarting an unsuccessful ECU unlock operation, it is possible (but rare) the ECU will have been left without an EcuTek licence. If this should occur, please use an additional license and contact EcuTek support to get your licence points balance corrected.