If All Keys Lost, and you are facing a problem with the ESL, below you can see the solution.
This situation happens when: the ESL does not communicate, there is a missing ESL, or it has already been replaced but not adapted. The key learning procedure would get stuck at around 90% and not continue.
The way through is to prepare a transponder from a dump of the SMT RH850 MCU.
Required equipment
| Licence | SB004 — Alarm OFF and Key Learning for Subaru Vehicles (MY 2021-2026) |
| Licence | SB003 — Key programming by RH850 dump and ESL reset/ synchronization |
- Abrites AVDI interface
- Abrites Diagnostics for Subaru software
- Abrites CB012 adapter - for the LIN (K-line) connection
- ZN085 RH850/V850 programmer - only if you have no working key
- A TA68 emulator
Procedure - no working key
1. Read the SMT on the bench
Remove the SMT unit and read its data flash on bench using the ZN085 RH850/V850 programmer, as the SMT contains an RH850 processor. You can find the required connection diagram directly in the RH850 software.
2. Prepare a TA68
Prepare a TA68 emulator from the Key Tool menu in the Subaru software.
3. Refit the SMT, connector still off
Install the SMT unit back in the car but keep it disconnected from the LIN (K-line) - that is, leave its connector off.
4. Connect to the LIN
Connect to the LIN using the CB012 adapter (the red cable).
5. Reset the steering lock
Reset the second hand steering lock from the ESL menu.
6. Disconnect the CB012
7. Connect the SMT unit's connector
8. Synchronise
Go to the Smart Key programming menu and select steering lock synchronization.
Procedure - working key available
Please note that you need to read the SMT unit on bench only if you do not have a working key.
- Disconnect the SMT unit from the connector
- Connect to the LIN using CB012 (the red cable)
- Reset the second hand steering lock from the ESL menu
- Disconnect CB012
- Connect the SMT unit (through its connector)
- Synchronize the steering lock to the car / SMT unit from the Smart Key Programming menu
Important notes
- The bench read is the expensive half, and it is avoidable. With a working key in hand you skip steps 1 and 2 entirely.
- The SMT must be physically fitted but electrically off the LIN while the steering lock is reset - that sequencing is the whole trick.
- A job stalling at 90% is the signature of this problem; it is not a software fault.
Troubleshooting
| Issue | Likely cause | Solution |
|---|---|---|
| Key learning stops at ~90% | ESL not communicating, missing, or replaced but not adapted | Run this adaptation procedure |
| The ESL reset does nothing | The SMT is still connected to the LIN | Disconnect the SMT connector before resetting |
| Synchronisation is unavailable | The SMT connector was not reconnected after the reset | Reconnect the SMT, then use steering lock synchronization |