Garmin GAD 43e Software Update for G500 TXi, G600, and G700: What Owners Should Check

What this update covers

According to Garmin's official service bulletin, software version 2.02 updates the autopilot disconnect logic when AC gyro emulations are being used. Garmin says this change allows the autopilot disconnect relay to disengage immediately when loss of AC reference voltage is detected.

The same Garmin notice says software version 2.03 fixes an ARINC 429 timing issue when the unit is receiving direct AHRS data from a GRS 7800. Garmin states that this fix is required for gyro emulation outputs to function in installations where GRS 7800 AHRS data is directly interfaced to ARINC 429 IN.

Products affected

Garmin identifies the affected equipment as GAD 43 and GAD 43e adapter units interfaced to G500(H), G600, and G700 systems.

This is not a broad Garmin-wide software notice. It is relevant to a specific adapter unit and a specific family of panel installations. That matters because owners usually search by the box name, panel family, or symptom first, not by bulletin number alone.

Is it mandatory?

Garmin lists the compliance status as optional and says the service document may be incorporated at the owner's discretion.

That does not mean it is irrelevant. If an aircraft has the exact configuration described in the notification, especially one involving AC gyro emulations or direct GRS 7800 AHRS data to ARINC 429 IN, this update may be worth reviewing during the next avionics visit or troubleshooting event.

What owners and operators should look at

A practical first step is to confirm whether the aircraft has a GAD 43 or GAD 43e installed as part of a G500(H), G600, or G700 TXi setup.

After that, the more specific question is whether the installation uses AC gyro emulations, direct GRS 7800 AHRS data, or other interfaces that match the scenarios Garmin describes. This is the kind of issue that often comes up during panel upgrades, autopilot troubleshooting, and avionics integration work, or general system review rather than during routine flying alone.

Because Garmin says these product changes can only be implemented through its authorized dealer and service center network, owners should plan around approved avionics support rather than treating this as a simple owner-performed update.

Warranty and service considerations

Garmin states that this modification is not warranty reimbursable.

The company also notes that the notification is not a substitute for the referenced documents used for airworthiness approval, and that separate installation airworthiness approval is still required for type certificated aircraft. In practice, that makes coordination more important. If an aircraft is already due for avionics work, troubleshooting, or scheduling around shop availability, it often makes sense to review related software updates at the same time rather than handling them as a separate event.

Planning downtime at KPTK

For aircraft owners coming through Oakland County International Airport (KPTK), a Garmin software update like this is often less about the document itself and more about coordinating the stop efficiently.

When avionics work is being scheduled through an authorized Garmin dealer, the surrounding logistics still matter. Arrival timing, aircraft staging, hangar coordination, and support during downtime can all make the process smoother.

If your aircraft is coming to KPTK for avionics troubleshooting, panel integration work, or a Garmin-related service visit, Michigan Aviation can help support the aircraft while that work is being coordinated.