Zumo User Forums

I left my XT on my bike for approximately 4 months. Not sure why it drained to the point of no return as the 12V supply is switched. I noticed this morning when I started the bike for the first time it didn’t power on, even after a few minutes with the engine running. I checked the holder voltage and it was good.

I then tried to charge it via a wall charger in the house where I can see the Current. It was trying to boot up but indicating 0.4A then it would shut off and show 0A. I kinda knew from experience the battery was drained beyond what the motherboard would tolerate for its boot process and charge. I find it strange the unit will not power up if the battery is goosed. I had a 595 previously and correct me if I’m wrong but I think that would boot up without a battery?!?

Anyway I took the screen off and disconnected the battery connector. The battery still had approx 2.3V so still recoverable. If the voltage drops way below its nominal 3.7V, say below 1Volt I would say it might be too far gone, maybe not. I’m just guessing here but the workable voltage range of the XT Battery is probably between 3.5 -3.7 Volts ie 0-100%. Anything below this is considered drained. The charging circuit probably shuts the unit down before this to protect the battery from draining excessively.

Morale of the story try and avoid your XT from lying around with a drained battery for extended periods.I think my issue was leaving the XT on the bike connected to the charger/holder and some parasitic battery drain occurred.

The good news is my XT seems to be fine now. Also the battery and screen replacement would appear to be pretty straight forward if you need to do that. One important point to remember is be extremely careful when disconnecting the Screens ribbon cable connector. If you break the black flip up part it’s literally game over for your GPS, I know this as it happened to myself years ago with an old Montana. The connector was brittle after years of use and it broke when I tried to lift it up. I remember trying to source the connector and failed miserably.

As i said before - it's important to know, that the Zumo XT does not shut down when it is in the motorbike cradle and the power cuts off!

What it does is, it goes into standby mode and with my experiences it lasts max. two weeks in this state - to completely turn off the Zumo XT you have to press the on/off button until a message box on the Zumo XT pops up and there you can switch off the Zumo XT completely. I never have any battery-related issues when shutting it down as described, even when the unit is not used for about 3-4 months....

The only time i personal work with the Zumo XTs standby-mode is when we are on our yearly motorbike-holidays in southern tyrol, because there i know that the Zumo XT is used every day and it is easier to hold it in standby mode to get a quicker sat-fix in the morning before leaving the hotel for one of our daily rides! But be sure that the cradle is used with a switched power line, because if not - you'll maybe get trouble with your bike's battery!

So even when you leave the Zumo XT in the cradle because the bike has its own garage - it's necessary to turn it off completely when its not in daily use...

Hey Robert. I agree with your comment 100%. I tested this out on my bike yesterday and it is indeed only in “stand-by mode” and not off completely when my ignition is turned off, hence why my XT was dead after I returned 4 months later. I have come back after 1-1.5 months before and it has still been useable.
But you are correct the XT must be shut down properly (long press the power button) when not in use. Seems a bit daft tho that the unit remains in stby mode until it kills its own battery. I’m sure Garmin could implement a software update which powers the unit down from stby mode after a week or so. I’m no programmer so not sure if that would be feasible.

Lithium batteries do not like to be fully discharged. The overall battery life is most likely compromised.
If I was going to the trouble of taking the Zumo apart I would have purchased a brand new battery and installed that rather than trying to resurrect the old one.

I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live: And whosoever liveth and believeth in me shall never die- said the power supply to the XT’s battery.

On a serious note: 2 weeks on the road and the XT is behaving without any battery issues on/off the mount. I agree with you if it’s left completely dead ie zero(ish) volts it would be a lost cause. I was lucky it still had over 2V.
Also it really isn’t that big of an issue to remove the screen, a few screws and a connector and your golden.

Posted this in the other thread too......

Update, I opened up the XT and the battery voltage is 3.8V. So I unplugged it from the motherboard and left it overnight, plugged it back in next day and now it won't boot up at all, even holding the power button 30 seconds to a minute, and whether I press bottom right screen or not. At least before I unplugged the battery I had the ability to see "GARMIN" on the screen with a scrollling strip underneath that indicated it was trying to do something....

Try connecting the USB cable to a 2A USB power source ? That should work - they have circuitry which allows charging and use at the same time. If it doesn't, I would suspect the USB connections on the circuit board. if

Also, try powering it in the cradle on the bike.