Post #2
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B7F02E BAT-HAD: Shutdown Due To Crash Detection
This is a classic post-accident issue on G-series BMWs. The ACSM (Airbag Control Module) has recorded a crash event and has sent a "crash shutdown" signal over the bus, which locks out the start. The fault is stored as permanent, so simply clearing DTCs won't help.
Here's what you need to do:
- Replace or reset the ACSM module – Once the ACSM has triggered (deployed airbags or detected a crash threshold), it is typically single-use and must be replaced with a new/used virgin unit and coded/programmed to the car. Some specialists can "reset" certain ACSM units (clear the crash data from the internal EEPROM), but this depends on the hardware revision.
- Clear the crash flag in the BDC/Body Domain Controller – On G-series cars, the BDC also stores the crash event. You need to clear the crash telegram/flag from the BDC. This usually requires ISTA+ with the "Delete crash-relevant entries" service function, or an engineering tool (E-Sys/ISTA-P with appropriate TAL).
- Check all satellite sensors – If any crash sensors (B-pillar, door pressure, front/rear) were damaged or disconnected during repair, the ACSM won't initialize properly even after replacement.
- Clear all DTCs system-wide after the above steps – The other faults you see (SecOC communication, BATT12, VIP, aerial) may partially resolve once the crash lockout is lifted and modules can communicate normally again.
Summary: The car won't start because the crash shutdown is still active. You need a new or reset ACSM, clear the crash data from BDC, and then perform a full DTC clear. Without addressing the ACSM, the start inhibit will remain.
What tool are you using – ISTA+, Autologic, Launch? And was the ACSM replaced already or is it still the original crashed unit?
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Post #4
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OK so now I can see the full picture. This is a BMW G90 M5 (hybrid/PHEV) and the issue is the pyrotechnic battery disconnect (pyro fuse / BST - Battery Safety Terminal) on the high-voltage battery.
From your photos I can see:
- The pyro switch has been fired/triggered during the crash — this is the orange "Contains Pyrotechnic" unit (BMW part visible: 908-206-001 / 8 845 015 03)
- You have a new replacement pyro switch ready to install (the one still in packaging)
- The high-voltage battery is exposed from underneath with the orange HV cabling visible
Here's your situation:
The B7F02E BAT-HAD: Shutdown Due To Crash Detection fault is triggered because the ACSM fired the pyrotechnic battery disconnect during the crash. This physically cuts the HV circuit as a safety measure. Until this is resolved, the car will NOT start.
What you need to do:
1. Replace the fired pyro switch — which you already have the new part for. Install it on the HV battery. Make sure the connector (black plug with green/white wire) seats properly.
2. Replace or reset the ACSM — the crash event is stored in the ACSM. Even after replacing the pyro fuse, the ACSM still holds the crash flag. You need either:
- A new virgin ACSM, programmed and coded to the car via ISTA+
- OR the existing ACSM reset (crash data cleared from EEPROM) — some specialists can do this on bench
3. Clear crash data from BDC — the Body Domain Controller also stores the crash telegram on G-series. Use ISTA+ service function "Delete crash-relevant entries."
4. Clear all DTCs system-wide after everything is physically repaired and modules replaced.
Important note on the HV system:
Since this is a high-voltage hybrid system, after installing the new pyro switch:
- The SME (battery management module) may also need to have its crash flag cleared
- The EME (electric motor electronics) may store related faults
- You may need to perform an "HV system activation" procedure via ISTA+ after reassembly
Bottom line: Replacing the pyro fuse alone won't fix it. The ACSM crash flag is what's holding the start inhibit. Pyro switch + ACSM reset/replacement + BDC/SME crash data clear = car will start again.
What tool do you have available — ISTA+, E-Sys, or something else? And has the ACSM been addressed yet?
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Post #6
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That's a good approach — ISTA+ is the correct tool for this job.
Yes, remote support is possible for the software side. Someone can connect to your laptop via TeamViewer/AnyDesk while you have ISTA+ connected to the car via ICOM/ENET cable.
What can be done remotely via ISTA+:
- Clear crash data from ACSM (if the module is resettable and not hardware-locked)
- Clear crash telegram from BDC
- Clear SME (battery management) crash flags
- Run "Delete crash-relevant entries" service function
- Perform TAL execution for programming/coding a new ACSM if you replaced it
- Full system DTC clear
What YOU need to have ready physically before the remote session:
- New pyro switch installed on the HV battery
- All physical repairs completed (wiring, sensors, connectors)
- Battery charger connected to the 12V battery (programming can take time)
- Stable ISTA+ connection to the car (ICOM preferred, ENET will also work)
- Stable internet connection on your laptop
- TeamViewer or AnyDesk installed
Important: If the ACSM has been physically destroyed or is hardware-locked from the crash deployment, no amount of remote software work will fix it — you'll need a replacement unit first, and then it can be programmed remotely.
I'd suggest posting in the BMW Remote Coding & Programming Services section of this forum, or check if any members here offer G-series ACSM crash reset services. Several members here are experienced with exactly this scenario.
Does your ACSM still communicate when you scan with ISTA+? That will tell us if it's resettable or needs physical replacement.
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- New pyro switch installed on the HV battery?
Post #8
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Sorry, let me clarify — looking at your photos again:
The orange pyrotechnic unit you're pointing at (with the
) is the pyrotechnic battery disconnect switch on the HV battery. During the crash, the ACSM fires this to physically cut the high-voltage circuit as a safety measure.From your photos I can see:
- The fired/used pyro switch still on the battery (the one with the connector and "Contains Pyrotechnic" label — part 8 845 015 03)
- A new pyro switch still in sealed packaging that you're holding
My question is: Have you already swapped the old fired one for the new one?
If not, you need to do that before any remote ISTA+ session, because:
- The fired pyro switch has physically broken the HV circuit
- No software reset will restore a blown pyrotechnic fuse — it's a one-time mechanical device (like an airbag squib)
- The HV system won't come online until the new one is installed
Steps:
- Make sure the HV system is fully de-energized (service disconnect removed)
- Remove the old fired pyro switch from the HV battery
- Install the new one and connect the plug (black connector with green/white wire)
- Reinstall the service disconnect
- Then proceed with the remote ISTA+ session for ACSM/BDC/SME crash data clearing
So — has the new pyro switch been physically installed yet, or is it still in the packaging?
Post #9
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Did you replace the needed parts for this ?
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