SU6 Beta 1.8.5.0 – Cessna 172 Steam Gauge: Transponder, KAP140 Autopilot and Clock remain unpowered after manual Cold & Dark start

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ISSUE DESCRIPTION

Description of the issue:After updating to SU6 Beta 1.8.5.0 (July 6, 2026), the default Cessna 172 Steam Gauge has an electrical initialization issue.

When starting from Cold & Dark using the normal checklist, the following instruments remain unpowered:

  • KAP140 Autopilot
  • Transponder
  • Digital Clock

However:

  • The same aircraft works correctly when starting with Ready to Fly.
  • Pressing CTRL+E immediately powers all affected instruments without any further action.

This suggests that the manual startup sequence is not correctly initializing one or more avionics/electrical buses.

FREQUENCY OF ISSUE

100% reproducible.

REPRODUCTION STEPS

Please list clear steps you took in order to help our test team reproduce the same issue:

  1. Launch MSFS 2024 SU6 Beta 1.8.5.0.

  2. Select the default Cessna 172 Steam Gauge.

  3. Start from a Cold & Dark parking position.

  4. Perform a normal manual engine start.

  5. Turn Battery, Alternator and Avionics Master ON.

  6. Observe that the KAP140, Transponder and Digital Clock remain blank.

  7. Press CTRL+E.

  8. All affected instruments immediately power on and work normally.

YOUR SETTINGS

If the issue still occurs with no mods and add-ons, please continue to report your issue. If not, please move this post to the User Support Hub.

What peripherals are you using, if relevant:

[PC Only] Are you using Developer Mode or have you made any changes to it?

[PC, MSFS 2020 Only] Are you using DX11 or DX12?

[PC Only] What GPU (Graphics Card) do you use?

[PC Only] What other relevant PC specs can you share?

MEDIA

Please add a screenshot or video of the issue occurring.

Moved to Sim Update 6 Beta | MSFS 2024 > Aircraft & Systems since beta related.

Are you starting C&D in walkaround mode or directly C&D into the cockpit using the new functionality ?

Because I have noticed some variation in default panel states with each, can you specify whether or not your Cold & Dark start begins from Walkaround mode or from the cockpit directly (with the new option in SU6)?

EDIT: @DementedCorn327 Beat me to the punch!

There are 2 avionics switches. One turns on the Garmins and the other the autopilot and transponder. It sounds like you still have one of them off.

Even when powered on, you still have to turn the knob on the transponder to turn it on.