Enable PMDG random failures through the CDU or aircraft menu, choose sensible rates, monitor active faults, reset them and avoid duplicate sim failures.
Enable PMDG random failures from the aircraft’s own PMDG Setup failure pages—normally reached through the CDU/FMC on modern Boeing products—not from the host simulator’s failure menu. Turn on the random or service-based mode offered by that model, set its rate, then use the same pages to review, clear or repair faults.
This is general rather than simulator-specific guidance: PMDG uses its own systems modelling in MSFS, Prepar3D and legacy FSX products. Menu labels and available failure modes differ between aircraft generations, while non-CDU aircraft use their own configuration interface.
Where is the PMDG random failures setting?
On most PMDG Boeing aircraft, the failure controls are inside PMDG Setup on the CDU/FMC.
- Power the aircraft and CDU. A dark CDU cannot display the PMDG configuration pages, so connect ground power or establish normal electrical power first.
- Open PMDG Setup. Press the CDU/FMC menu key, select PMDG Setup, then look for FAILURES or a random/service-based failures option within the aircraft’s simulation settings.
- Select the failure method. Enable Random Failures or Service-Based Failures if that model provides the option. If the page lists only individual faults, the aircraft may support manual or armed failures without a global random generator.
- Set the frequency. Some products present a rate, probability or mean time between failures (MTBF). A lower MTBF means more frequent faults; a higher MTBF makes them less likely. Keep any maximum-failure limit low until you know how the system behaves.
- Confirm the active configuration. PMDG options may be stored for a particular airframe, registration or aircraft profile. Recheck the failure setting after changing liveries, loading a panel state or reinstalling the aircraft.
- Disable competing failure sources. Remove scheduled failures from the host simulator and avoid running a separate random-failure injector at the same time. Generic simulator faults do not always map cleanly onto PMDG’s custom systems.
Our explanation of how simulator-level and aircraft-specific failure engines can overlap covers why two active generators often produce confusing or duplicated symptoms.
Which PMDG failure mode should I choose?
Use random or service-based failures for operational unpredictability, but choose a manual or armed fault when practising a specific procedure.
| Mode | Best use | What to expect |
|---|---|---|
| Manual or active | Testing one known malfunction | The selected fault starts immediately. |
| Armed or triggered | Checklist and crew training | The fault occurs after a supported time, phase or condition. |
| Random | Unpredictable line operations | The aircraft selects faults according to its configured rate. |
| Service-based | Persistent airframe use | Failures are influenced by the model’s operating or maintenance state. |
Realistic rates can produce many completely normal flights. If you need an engine failure during one session, random mode is the wrong tool: arm or activate the fault deliberately instead. Our staged engine-failure practice plan explains how to introduce faults without turning the exercise into guesswork.
How do I monitor and clear an active PMDG failure?
Use the PMDG failure pages to identify the initiating fault, then manage the aircraft through its normal warning system and checklist before resetting anything.
- Observe the first indication. Master cautions, EICAS messages, system synoptics and abnormal instrument readings reveal what the aircraft detected. Several later warnings may be consequences of one original fault rather than separate random failures.
- Check the failure status page. Look for active, armed or service-required entries. Turning random generation off normally prevents new faults; it does not necessarily remove one that is already active.
- Run the applicable procedure. Treat the event as an aircraft malfunction. Clearing it from the menu before completing the checklist removes most of the training value.
- Clear or repair the fault after the exercise. Use the individual reset, clear-all or maintenance/service command provided by that PMDG model. The wording differs between products.
- Restore the aircraft’s systems. Removing the simulated failure does not automatically restart a shut-down engine, recharge a depleted battery or restore hydraulic pressure. Reconfigure or restart the affected system normally.
Will PMDG failures carry over to the next flight?
They can carry over when the aircraft uses a persistent service state or when an active fault was saved with the configuration. A panel-state save and a maintenance state are not necessarily the same thing, so verify that the failure page shows no active faults before beginning a normal flight.
If a cleared fault returns immediately, use the aircraft’s service or repair function and load a known clean state if required. Simply switching the random generator off may leave the original malfunction in place.
Why are PMDG random failures not working?
Most apparent faults come from an unrealistic rate, an unpowered interface, persistent saved failures or another failure engine operating alongside PMDG.
- No failures occur: realistic MTBF settings may allow dozens of uneventful hours. Reduce the MTBF or increase the rate for testing, or activate a specific fault manually.
- Failures happen constantly: check that the MTBF scale has not been interpreted backwards, reduce the permitted rate and disable host-simulator failures.
- The failure menu is missing: confirm that the loaded aircraft and product generation support that mode. Some PMDG models expose only individual failures or use a different configuration interface.
- A warning remains after clearing: the underlying aircraft state still needs attention. Restore pumps, generators, bleed sources or engine operation as the checklist requires.
- Controls are blank or behave incorrectly: update the product before rebuilding profiles or reinstalling files. Follow our instructions for bringing PMDG aircraft and Operations Center up to date safely.
- The apparent failure is not listed: check switch positions and normal configuration first. Incorrect fuel pumps, hydraulics, bleed-air controls, IRS alignment or electrical sources can reproduce convincing failure symptoms without any injected fault.