Hobbs reset to zero.

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Michael Aarons
Posts: 1
Joined: Thu Jan 20, 2022 6:15 am

Hobbs reset to zero.

Post by Michael Aarons »

I did a firmware update on my IEFIS Lite.
All Hobbs and other timers reset to zero.
Is this usual? Will other settings have changed?
Can I go into the setup menu and restore them?
rainier
Site Admin
Posts: 662
Joined: Fri Aug 28, 2020 7:03 pm

Re: Hobbs reset to zero.

Post by rainier »

This is not something related to a firmware upgrade.

Your EFIS has a small battery backed memory that is supplied by a CR2032 coin cell (or rechargeable NiMH in newer models). This is then backed up by your "keep Alive" connection on the back of your instrument - this is supposed to be a permanent connection to your aircraft's batteries positive terminal. Not switched - always there (a fuse is of course, as always, recommended).
The KA connection takes a few micro-amps of power and supplies the memory so the batteries don't have to.

This memory stores quite a few things that can change frequently - but not anything you will find under your setup menu.

You can enter Hobbs and other timer values in your Time and Date items setup menu (under the system setup menu).

I would recommend you check your KA connection to make sure you have a permanent supply there. If your EFIS has the CR2032, replace that too as it is discharged.
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