TIA Portal V14 HMI Simulation Not Starting: KTP/TP Panel Fix

Problem Overview

Engineers commissioning TIA Portal V14 projects with a SIMATIC S7-1200 or S7-1500 controller frequently report a failure mode in which the toolbar entry Start Simulation is present for the PLC window but is missing, greyed out, or non-functional inside the HMI window. The same project may simulate correctly on a colleague's workstation, ruling out project logic. The two recurring complaints are:

1. The HMI toolbar's Start Simulation command does not appear at all when the HMI device editor is active.
2. The HMI simulation launches but tags remain frozen at initial values instead of mirroring the live PLC process image that was previously visible.

Both symptoms point to either (a) a missing/disabled WinCC Runtime Simulation component, (b) an HMI firmware version that is not within the device catalog range supported by TIA V14, or (c) a connection configuration that does not point the simulated Runtime at the live S7 controller's PG/PC interface.

Affected Software and Devices

Root Cause Analysis

Three primary failure paths produce the observed behaviour. Diagnose them in order, as each one masks the next.

Cause 1 — WinCC Runtime Simulation Not Installed or Locked

The HMI simulation is a separate Windows service / executable (HMIRTM.exe) launched by the engineering tool. If the TIA Portal installer was run with the Custom option and WinCC Runtime Simulation was unchecked, the Start Simulation button is hidden in the toolbar. The same symptom occurs if the component is installed but its licence is in trial-expiry state or the simulation service is stopped by group policy.

Cause 2 — Project / Firmware Mismatch

When a project is opened that was last saved against an older TIA Portal version (e.g. V12 or V13), the HMI device may retain an older firmware descriptor (FW V12.0.0.0 for a KTP600 Basic). TIA V14 refuses to compile a runtime image for that firmware and disables the simulation. The PLC simulation continues to work because the S7-1200 CPU family retains forward compatibility with the older catalog descriptors.

Cause 3 — HMI–PLC Connection Points at "Internal" Instead of PG/PC Interface

The second reported symptom — simulation no longer reading live PLC values — typically follows a project upgrade or a manual edit of the HMI's Connections table. The runtime was previously bound to the PLCSIM / S7ONLINE access point of the engineering PC; an upgrade can reset this to Internal — no partner, which causes the simulated Runtime to drive its own tag memory rather than exchanging with the simulated or real PLC.

Diagnostic Procedure

Run through the following checks before changing any project data. Each step is non-destructive.

1. Verify the installation. Open Start > All Programs > Siemens Automation > TIA Portal V14 and launch Detailed information about installed software. Scroll to the bottom of the list and confirm the line SIMATIC WinCC Runtime Simulation V14.0 (or V14.0.1) is present and Status: Installed.
2. Confirm the PG/PC interface assignment. Open Control Panel > Set PG/PC Interface. The access point S7ONLINE must point to PLCSIM (PROFIBUS/MPI/PROFINET) <your NIC> or, for Ethernet-only setups, to the TCP/IP interface of the engineering machine.
3. Inspect the HMI device firmware. In the project tree, right-click the HMI device, choose Properties > General > Device & Network Editor > Catalog, and read the firmware field. Cross-reference it with the table in section "Affected Software and Devices".
4. Inspect the connection direction. In the HMI device, open Connections. The Partner column for the S7 connection must be the PLC's PROFINET name (e.g. plc_1) — not the placeholder (Internal).
5. Confirm the toolbar is not filtered. Right-click the HMI editor toolbar and ensure Simulation is checked. A hidden toolbar group will silently suppress the Start button on some TIA V14 builds.

Step-by-Step Solutions

Solution A — Reinstall or Repair WinCC Runtime Simulation

1. Close TIA Portal completely. End the process S7TGTOPX.exe in Task Manager if present.
2. Mount the original TIA V14 DVD / ISO. Right-click Setup.exe and run as administrator.
3. Choose Modify / Repair. Tick WinCC Runtime Simulation in the component tree (path: WinCC > WinCC Runtime > WinCC Runtime Simulation).
4. Complete the wizard and reboot. Re-open the project and confirm that the Start Simulation icon (▶ with a small HMI glyph) is now visible in the HMI editor toolbar.
5. If the line was already present, choose Repair instead. This re-registers the COM components HMIRtm.Comp and WcRtm.dll.

Solution B — Migrate an Older HMI Firmware Descriptor

1. In the project tree, right-click the HMI device and select Change device / version.
2. Select the same panel model with firmware V14.0.x from the catalog (e.g. 6AV2 124-1MC01-0AX0 for KTP600 Basic color DP).
3. Click OK and accept the conversion dialog. TIA will recompile the runtime image.
4. Re-open the HMI editor and verify that the Start Simulation command is now active.

Solution C — Rebind the HMI Connection to the Live PG/PC Interface

1. In the HMI device, open Connections and double-click the S7 connection used by the simulation.
2. Set Partner: PLC_1 (the actual PROFINET device name of the S7-1200 / S7-1500 you are simulating).
3. Set Interface: PROFINET (Ethernet) or the protocol your PG/PC interface is bound to.
4. Compile the HMI project (Right-click HMI > Compile > Software (rebuild all)).
5. Start the PLC simulation first (toolbar ▶ on the PLC window), then the HMI simulation (toolbar ▶ on the HMI window). The Runtime will now use the PG/PC interface and exchange live values.

Firmware / Software Compatibility Matrix

A V12 KTP600 project opened in TIA V14 will still load, but the simulation toolbar will be disabled until the firmware descriptor is upgraded (see Solution B).

Verification Procedure

1. Open the project. Click the HMI device in the project tree. Confirm the toolbar shows Start Simulation (icon: play arrow with HMI display).
2. Start the PLC simulation first. The instance indicator at the bottom of the TIA window should read PLCSIM V14 — Running.
3. Click Start Simulation on the HMI editor. A window titled WinCC Runtime Simulation should open and display the configured start screen of the HMI.
4. In the simulated HMI, force a tag (e.g. "Motor_Start") from a screen button. The value should propagate to the watched tag in the PLC's monitoring table within 100 ms (default update cycle for non-cyclic tags).
5. Stop the simulation in reverse order (HMI first, then PLC). Both indicators should return to Stopped.

Edge Cases and Field Notes

• Two PG/PC interfaces active. When a CP5711 (PROFIBUS) and an Intel NIC are both bound to S7ONLINE, TIA V14 will silently route the HMI Runtime to the wrong interface. Open Set PG/PC Interface and isolate the desired one.
• Antivirus interaction. Some endpoint protection suites quarantine HMIRTM.exe on first launch, which produces a "simulation start failed" message with no error code. Add the TIA install directory to the AV exclusion list.
• Remote desktop sessions. WinCC Runtime Simulation does not render in a non-interactive RDP session. Connect to the engineering PC with console access or use mstsc /admin.
• Multiuser / TIA Portal Multiuser Server. If the project is checked out from a multiuser server, only the session that holds the write lock can start the simulation. Read-only sessions see the Start button greyed out.
• TP1500 Comfort with three S7-1515 CPUs. When multiple PLCs are configured in one HMI project, the connection to each PLC must be set up separately. A common pitfall is leaving the third PLC's Partner set to (Internal) after a copy-paste of an existing connection.
• KTP600 firmware V12 is a hard stop. KTP600 Basic panels shipped with firmware V12 cannot be brought up under TIA V14 simulation. A control panel upgrade (WinCC flexible / TIA Panel Image Updater) to V14 is required at the panel itself before the PC-side simulation can be configured.

Troubleshooting Matrix

Preventive Measures

• Pin the TIA Portal version and the HMI firmware version in the project header. Document the RT Simulation build number from Help > Detailed information.
• Use a single engineering image (golden image) for the team so that install drift does not introduce simulation regressions.
• Always start the PLC simulation before the HMI simulation. The Runtime is a client of the simulated PLC and will not establish its connection otherwise.
• After any project upgrade, re-validate the Connections table of every HMI device before commissioning.

Related References

For deeper background, consult the official TIA Portal V14 documentation set:

• SIMATIC TIA Portal V14 — WinCC Runtime Simulation entry
• SIMATIC HMI KTP600 Basic operating instructions
• SIMATIC TIA Portal V14 — Function Manual HMI Commissioning
• SIMATIC TP1500 Comfort product information