Resolving FM 458-1 DP Stop LED Flash with BIOS Error 1800

Problem Overview

The SIMATIC FM 458-1 DP (6DD1 607-0AA2) is a high-performance technology module that slots into an S7-400 rack and executes closed-loop control, motion, and custom algorithm charts compiled with D7-SYS / CFC. When the module powers up, the application program and runtime BIOS are read from the on-board micro memory card (MMC). If the MMC contents become unreadable, the FM 458-1 DP cannot complete initialization, the STOP LED flashes at ~1 Hz, the module disappears from the S7-400 hardware catalog online view, and any attempt to download charts produces the message:

1800: The BIOS system file not found

The user CPU (for example, 6ES7 416-2XN05-0AB0, firmware V5.3.1, or 6ES7 414-2XG03-0AB0) continues to run normally and remains reachable over MPI/ISO-on-TCP, but the FM is reported as "not available" in HW Config. The chart-download path Target system → Download from CFC also fails because the underlying S7DOS connection to the FM cannot be established.

Affected Hardware and Firmware

Root Cause Analysis

The flashing STOP LED combined with error 1800: The BIOS system file not found is the diagnostic fingerprint of a corrupted or unformatted micro memory card. The FM 458-1 DP stores three artefacts on its MMC:

1. The runtime BIOS image (firmware), shipped from Siemens as a BIN file.
2. The compiled CFC chart set, output by the D7-SYS compiler (*.bin / *.f7b blocks).
3. Retain / persistent data (initial values, parameter sets, PID state).

If the file system on the MMC becomes inconsistent — typically because the card was previously written in a third-party card reader, was hot-swapped, was formatted as FAT with a non-industrial cluster size, or suffered a power-loss during chart download — the FM's boot loader cannot locate the BIOS file, and the application CPU never gets the chance to load charts. The result is INIT_ERR bit 0x8000 ("No user program; configuration not loaded") in the CFC module-information dialog.

Second, even after the MMC is repaired, the engineering workstation must use a D7-SYS version that matches the CFC version referenced by the project. A mismatch between D7-SYS 6.2 SP3 and D7-SYS 7.0 will compile a chart set that the FM's runtime rejects, producing a different "module not available" symptom. Always consult the Siemens compatibility list shipped under Start → SIMATIC → Information → English → STEP 7 - Compatibility List.

Pre-Diagnostic: What the LEDs Tell You

Diagnostic Procedure 1 - CFC Module Information (INIT_ERR / SYS_ERR)

The most authoritative read-back of the FM's internal state is through the CFC chart running in the S7 CPU that owns the FM slot. This works even when HW Config shows the FM as not available, because the S7 CPU-to-FM link goes through the S7-400 backplane and is independent of the routing that HW Config uses.

1. Remove the MMC from the FM 458-1 DP and reinsert the rack power (CPU should run, FM should boot to BIOS loader and report "No user program"). This step forces the FM into a state where it responds to the CFC module-information request without hanging the chart download.
2. Open the S7 project, expand the FM 458-1 DP in the component view, and double-click any chart (even an empty @SIMD-only chart) to launch CFC.
3. From the CFC menu select CPU → Module information.... The dialog reports the system error panels listed in the table below.

INIT_ERR 0x8000 is the value that maps directly to BIOS error 1800. It tells the engineer that the runtime is alive, the backplane is healthy, and only the chart/MMC load step has failed — which is the precondition for the MMC-recovery procedure below.

Diagnostic Procedure 2 - Serial Console on the FM

For a deeper, off-line view of the FM's boot sequence, connect a PC with a real RS-232 port (COM1 or COM2) to one of the two 9-pin Sub-D connectors on the FM front panel. The two connectors are wired as a null-modem pair (2-3, 3-2, 5-5). Use a terminal program configured as follows:

• Baud rate: 19200 bit/s
• Data bits: 8
• Parity: even
• Stop bits: 1
• Flow control: none

On power-up the FM prints the banner Hallo, ich lebe !! ("Hello, I am alive !!") followed by BIOS revision, slot number, and a list of detected MMC partitions. If the banner appears but the partition list is empty or the BIOS load is aborted, the MMC file system is the fault. If the banner does not appear at all, the FM main board is suspect and the module should be replaced.

Diagnostic Procedure 3 - PG/PC Interface Reset

Before chasing the MMC, rule out a corrupted PC-side communication stack. Reset the PG/PC interface to factory defaults:

1. Launch C:\Program Files\Siemens\Step7\S7BIN\p7sdonlx.exe
2. Select PG/PC as the access point.
3. Click OK to write the default S7ONLINE access path.

This step clears broken TCP/IP routing entries that sometimes prevent HW Config from re-discovering the FM after a slot change.

Step-by-Step Resolution

1. Power down the S7-400 rack and remove the MMC from the FM 458-1 DP. The MMC is the small card in the slot behind the front cover; eject it carefully with the slider. Inspect the contacts for oxidation. Do not bend the ejector.
2. Format the MMC in a Siemens Field PG using the SIMATIC MMCFormatter (delivered with STEP 7 / PCS 7 under Start → SIMATIC → STEP 7 → S7-PCT or the standalone mmc_formatter.exe in the STEP 7 tools folder). Use the SIMATIC MMC option, not the generic Windows format; this writes the correct boot-sector header that the FM BIOS expects. Allow the format to complete (typically < 30 s for a 2 MB card).
3. If the MMC is mechanically suspect, replace it with a new 6ES7 953-8LL20-0AA0 (2 MB) card. Larger MMCs (4 MB, 8 MB) are also accepted by FM 458-1 DP, but the project must be small enough to fit.
4. Reload the BIOS onto the MMC. Insert the freshly formatted card, power the rack, and use the FM 458-1 DP download dialog (called from HW Config: right-click the FM → Object properties → Download BIOS or via the menu Target system → FM 458-1 DP → Download BIOS). The download takes 30-60 s and the STOP LED transitions from slow flash to a faster flicker, then to solid yellow when the BIOS is in place.
5. Verify the BIOS banner on the serial console (19200/8E1). The next reboot must show Hallo, ich lebe !! followed by the BIOS revision string and the slot address. If only the banner appears, proceed.
6. Compile the CFC project. Even an otherwise empty FM chart must be compiled so the FM sees a valid configuration block. Use CFC → Chart → Compile → Charts of the AS (or the menu item shown in your localized STEP 7). Confirm the D7-SYS version on the menu Help → Info → D7-SYS matches the PCS 7 / CFC version of the project (see compatibility section below).
7. Download the compiled charts to the FM. In CFC select CPU → Download. The chart set is streamed to the MMC and unpacked by the FM. Successful download is reported in the CFC log window; failure modes produce the same "module not available" message and re-trigger the STOP flash.
8. Watch the LEDs during download. The yellow STOP LED stays lit while the chart set is being written, the green RUN LED blinks on each chart task, and the red SF LED must remain off. After the last chart, the FM switches to RUN (green solid) and the CFC online view shows all tasks OK.

Engineering Tool Compatibility (D7-SYS / CFC / PCS 7)

The D7-SYS add-on package must be at the same major version line as the CFC blocks used in the project. The matrix below is distilled from the STEP 7 / PCS 7 compatibility list:

Mixing D7-SYS 6.2 SP3 with a CFC compiled under PCS 7 V7.1 (which expects D7-SYS 7.1) will compile but the FM will reject the chart set with INIT_ERR 0x8000, mimicking an MMC fault. Always upgrade D7-SYS to match the CFC version before suspecting the MMC.

Communication Path Sanity Checks

Even with a healthy MMC, the FM download will fail if the engineering PC cannot reach the S7 CPU. The PC has two standard paths to the rack:

1. ISO-on-TCP via CP 443-1: configure the PC's IE General access point to the CP 443-1's MAC or IP, set the TSAP to 03.01, and verify with Accessible nodes in HW Config.
2. MPI via PC Adapter (USB or RS-232): set the PG/PC interface to PC Adapter (MPI) or PC Adapter (Auto), leave the MPI address at 0 and the bus profile at 187.5 kbit/s unless the rack profile is known to differ.

Both paths were attempted in the original fault report and both produced the same MMC-derived symptom. If the S7 CPU is reachable in Accessible nodes but the FM still shows as not available, the MMC is the dominant cause, not the communication path.

Hardware Catalog and HSP Notes

FM 458-1 DP catalog entries are shipped through Hardware Support Packages (HSP), not through Internet GSD updates. To bring a fresh FM 458-1 DP into the hardware catalog:

1. Open HW Config and select Options → Install HW Updates (or in older STEP 7: Options → Edit HSP).
2. Point the dialog to the Siemens HSP archive downloaded from the Siemens Industry Online Support portal. The HSP for FM 458-1 DP is usually named hspxxxx.zip and includes both V2.0 and V2.1 module entries.
3. Restart HW Config. The FM 458-1 DP now appears under SIMATIC 400 → FM-INSERT → FM 458-1 DP with the version selectable in the drop-down.

The GSD file mentioned in the original report is only relevant if the FM 458-1 DP is operated as a DP slave on a third-party PROFIBUS master. For the standard S7-400 slot configuration, the GSD is unused.

Verification

After MMC recovery and chart download, confirm the fault is closed with the following checks:

• FM 458-1 DP STOP LED off, green RUN LED solid on, no red SF or BF LEDs.
• HW Config online view shows the FM as Available with the correct order number (6DD1 607-0AA2) and firmware version (V2.1).
• CFC → CPU → Module information reports INIT_ERR 0x0000 and SYS_ERR 0x0000.
• Serial console prints Hallo, ich lebe !! and the BIOS revision on every rack power-up.
• CFC online mode shows all task time slices (T1..T5) within their configured cycle times and no user errors in the diagnostics view.

Troubleshooting Matrix

Field-Proven Caveats

• Always format the MMC in a Siemens Field PG (or use the SIMATIC MMC Formatter). A Windows format writes a FAT12/16 header that the FM BIOS does not always recognize, and the symptom is identical to a bad card.
• Do not interrupt a chart download. Power loss during the final 10% of a download can corrupt the chart archive in a way that the next boot cannot recover; the BIOS will then report 1800 again. Always perform downloads with a UPS on the rack.
• The MMC 6ES7 953-8LL20-0AA0 (2 MB) is the smallest part qualified for FM 458-1 DP. Smaller cards (1 MB) are not supported and will be rejected by the boot loader.
• When upgrading from D7-SYS 6.2 SP3 to D7-SYS 7.0, run a full project compile before attempting the first chart download. The block signature changes, and the FM will not run mixed-version charts.
• For an introduction to the FM 458-1 DP download workflow, see the Siemens Getting Started with FM 458-1 DP (PDF) document, which covers both online and offline download paths.

FAQ