Question

FMB920 owner manual states 2mA power consumption when device is in Ultra Deep Sleep mode.

I tried to measure and verify those values before I connect to the vehicle.

The lowest value I got is 5mA@12V.

Device definitely enter ultra deep sleep mode: LEDs stops blinking, bluetooth interface closes connections and stop advertising..., but current value remains about 5mA.

Any suggestions what setting to check?

Answer 1

Hello,

Thank you for your query.

Could you provide more detailed testing environment? Only power supply connected? Can you confirm that USB cable is disconnected from device and amperage is measured after? Ultra deep sleep does not depend on configuration, it shuts down most of components that drains a lot of energy. Please confirm if USB is connected to the device. Thank you.

Best regards,

Teltonika Support.

Comments

Hello,

I'm testing the device on the desk. The power supply is a fully charged UPS battery (about 13V).

Only the power line is connected (red and black wire), no additional devices.

No USB connection.

Answer 2

I have the exact same problem. FMB920 set up on desk, running from a bench 12V power supply. The only things connected are red and black for power, no USB connected. The device pulls just under 6mA in deep sleep mode, confirmed using a calibrated multimeter and again on the ammeter on the bench power supply. The figures quoted on the Teltonika spec sheet are just not true, and this is a big problem for me as I wanted to use this tracker on an item of plant that is rarely used, so 6mA is far too high!

Comments

Try to remove the SIM card and repeat the current measurement without the card.

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Interesting. I have tried with the SIM removed and the sleep current is indeed 2mA. So the question is, what can be done to reduce sleep current while the SIM is installed? Removing it isn't exactly practical, and I would have expected the hardware to remove power to any non-essential items during deep sleep, so I don't understand why the SIM card would even be receiving power.

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I had the same strange case.

Removing and inserting the SIM card solved the problem.

Maybe it's a bug in the software and I hope it won't happen again.

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I have no idea how you ever figured that out, but you sir, are a genius! Removing and re-inserting the SIM card did the trick, now down to 2mA @ 12V in sleep mode. Thank you!