G-Series · Pre-June 2020
In-house unlock
All pre-June 2020 G-series cars require an unlock — but it can be done in-house at our HQ.
- · Unlock required
- · In-house at our HQ
- · No need to send the ECU away
Locked ECU?
Here’s what to do.
Modern BMW ECUs are protected by multiple layers of security. If yours is locked, it must be unlocked before any tuning can take place. This guide explains which ECUs need unlocking, the type of unlock required, and how to get it done.
Chapter 01
Why ECU unlocking is required
BMW introduced enhanced ECU protection across newer models to prevent modification.
- 01
Locked ECUs cannot be written to via OBD or standard bench tools
- 02
Affects most modern Bosch MG1 (petrol) and MD1 (diesel) ECUs
- 03
Unlocking removes these restrictions and enables full access for calibration
Chapter 02
Which BMWs require unlocking?
G-Series · Post-June 2020
FEMTO / Autotuner
Newer G-series cars require an unlock at boot level — the ECU must be removed and sent away.
- · Unlock required
- · FEMTO or Autotuner unlock
- · ECU shipped for processing
Late F-Series M2 / M3 / M4
In-house unlock
Certain late M2 / M3 / M4 cars equipped with Bosch MED17.2.G ECUs require unlocking — but this can be done in-house.
- · Unlock required
- · In-house, no FEMTO/Autotuner needed
- · Post to us or visit HQ
Quick reference
Vehicle / unlock method
| Vehicle type | Unlock required | Method |
|---|---|---|
| G-Series · Pre-June 2020 | Yes | In-house |
| G-Series · Post-June 2020 | Yes | FEMTO / Autotuner |
| Late M2 / M3 / M4 (MED17.2.G) | Yes | In-house |
Chapter 03
Unlock methods explained
Method A
In-house unlock
HQ or postal
For pre-June 2020 G-series and MED17.2.G ECUs in late M cars.
- · ECU removed from vehicle
- · Unlocked using specialist tools
- · Returned ready for flashing
Method B
FEMTO unlock
Post-June 2020 ECUs
Boot-level unlock performed off the car.
- · ECU must be physically removed
- · Sent away for unlocking
- · Performed at boot level
- · Once complete, fully writable
Method C
Autotuner unlock
Alternative to FEMTO
Same approach as FEMTO, different tool — full read/write access once complete.
- · ECU removed and shipped
- · Sent off for unlocking
- · Enables full read/write access
- · Compatible with standard tuning tools after unlock
Not sure which yours needs?
Check the
build date.
The build date is on the driver-side door label. As a rule:
- · Pre-June 2020 → In-house unlock
- · Post-June 2020 → FEMTO / Autotuner unlock
If you’re unsure, send a photo of the door label and Samuel will confirm for you.
ECU removal
The ECU must come out.
Required for all unlock types. The car will not run while the ECU is out.
Removal can be done by
- 01
Yourself
- 02
A local garage
- 03
At our HQ — 117Speed
Your options
Two ways forward.
Option 01 · Postal
Send your ECU to us
Remove the ECU and ship it securely. We handle the unlock process and return it to you ready for installation.
Arrange shippingOption 02 · Visit HQ
Bring the car to 117Speed
ECU removed on-site, unlocked in-house where applicable, or prepared and processed for FEMTO / Autotuner. Walk away with a writable ECU.
About 117SpeedImportant notes
A few things to know.
- 01
Unlocking is required before any tuning can begin
- 02
It does not add power on its own
- 03
Once unlocked, the ECU remains accessible for future flashing
- 04
Turnaround time depends on ECU type and unlock method
Start the unlock
Tell us about
your car.
Send the basics and Samuel will confirm which unlock method applies and what the next step is.
Next step
Remove the ECU,
or arrange to bring the car in.
Once unlocked, the ECU is fully accessible and ready for use with supported tuning platforms.