This article provides a step-by-step guide on how to reset the crash data for an SGMW R7F701A033 encrypted Airbag ECU using OBDSTAR P50. This procedure is necessary when standard diagnostic tools cannot clear crash-related fault codes.
Required Tools & Equipment
P50 or Keymaster G3
High-power DC regulated power supply
MP001 multi-function programmer
RH850/V850 adapter kit
Main cable and jumper
SGMW R7F701A033 airbag module
Pre-Operation Preparation
1. Software Upgrade: Ensure your diagnostic tool’s software is updated to the latest version.
2. Navigation: From the main menu, select [Crash Reset] and then [AIRBAG RESET].
3. Model Selection: You can quickly locate the correct option by searching for the airbag ECU part number in the upper-right corner search bar.
4. Initial Setup: Select the correct Boot Mode and the corresponding RH850 adapter.
Critical Preliminary Step: Review the Guide
Before any physical work, carefully review the built-in instructions.
Tap the [Guide] button.
Thoroughly read all sections: Background, Menu Description, Operation Description, Notes, and Connection Method.
This information is crucial for a successful and safe reset.
Hardware Connection & Wiring
1. Click [Connector Pinout].
2. Important: This specific ECU has multiple wiring methods. You must follow the pinout diagram that matches the function you are performing.
3. Connect the wires from your programmer to the ECU’s circuit board precisely as shown in the diagram.
Step-by-Step Reset Procedure
Phase 1: Initial Diagnostics & Preparation
1. ECU Information: Click [ECU Info] to read and verify the ECU’s part number.
2. Check for DTCs: Select [Read DTC]. You will see a persistent crash-related fault code.
3. Attempt Erasure: Choose [Erase DTC]. This will fail, confirming the need for a physical reset.
Phase 2: Physical Access & Data Backup
1. Initiate Crash Erase: Select the [Erase Crash (MP001)] function.
2. Power Down: Tap [PCB Pinout] to view the diagram, then disconnect power to the ECU.
3. Disassemble: Remove the cover of the airbag ECU to access the main printed circuit board (PCB).
4. Adapter & Wiring: Replace the standard adapter with the RH850 adapter. Solder the wires to the ECU’s PCB as shown in the diagram.
5. Read All Data: Tap [Read All Data (R7F701A033)] and then [START].
6. Connect Programmer: Connect the MP001 programmer to the diagnostic device. An “Upgrade successful” message will appear.
7. Acknowledge Risk: A warning will appear: “Continuing with the risk of locking the MCU, do you want to continue?” Proceed with caution.
8. Create Backup: The tool will read the ECU’s memory. It is critical to save the backup file when prompted. Wait for the “Operation success” message.
Phase 3: Erasing the Crash Record
1. Execute Erase: Click the [Erase Crash] button.
2. Confirmation Prompt: The device will ask, “Has the [Read All Data] function been executed?” Since you have already done this, select OK.
3. Select Backup File: When prompted, select the data file you saved in the previous step.
4. Completion: The process will complete with a “Crash record erased successfully” message.
Phase 4: Final Verification
1. Reconnect: Reconnect the device to the vehicle and switch the software back to standard diagnostic mode.
2. Clear DTCs: Select [Erase DTC] again. The DTCs will now be erased successfully.
3. Final Check: Perform a final [Read DTC] to confirm. The previous crash record and all related fault codes will be gone.
Conclusion
You have now successfully used the OBDSTAR P50 to reset the collision data for the SGMW R7F701A033 airbag ECU. Always ensure a full backup is performed before attempting any write operations to prevent permanent ECU damage.
For more details, you can refer to this video:
