Toobuilder

Toobuilder

Well Known Member
My 396 is having increasing trouble finding the satellite constellation on bootup. Switching from the remote to the fixed antenna changes nothing, nor does repeated power cycles. Sometimes, I'll force it to "keep searching" and it will eventually lock up, but lately it stays lost. All this in spite of the 296 in the back seat happily locked in solid from power on. My avionics guy suggested the "hard reboot" (which dumps the history) and that worked... for a day.

What's the deal? Am I looking at an expensive trip back to Garmin, or is there another fix?

Thanks
 
Sounds like its a clock battery that is dead. It should however eventually get a lock even with a bad battery. It should also hold a lock once it gets a initial position even with a bad battery. Could take 8 to 10 minutes to get that initial lock if it is the battery. There were some posts here on how to change it out without sending it back to Garmin if in fact its the battery.
George

Here is some info from another post.
http://www.vansairforce.com/community/showthread.php?t=71280&highlight=clock+battery
 
Last edited:
Dead backup battery for sure.

This is a design flaw....Very poor design...one of the only ones I know of for the x96 series.

The latest firmware has some features that are suppose to minimize the pain that this battery can cause when it dies.

Best to replace it, if you do it will work like new again.

Replacing the battery is not for the faint at heart and I do not recommend it unless you are really good at soldering small surface mount electronics. You basically have to tear the whole thing apart to get to the battery.
 
Last edited:
Battery replacement

I did my 296 a few years ago. You have to carefully dig into the unit, and you will find a watch type battery. I did this with a friends help and it was simple, but did require some soldering skill. We went with a larger than stock battery with the same voltage. The 296 was not designed to easily take apart, but was not that hard. I think we saved between $150 and $200, which a lot of manufactures use as their standard repair fee.

Steve Barnes "The Builders Coach"
 
Its certainly is a bad design feature. Garmin seems to have the same setup in all their marine GPS's. Its a real pain when the battery dies. I don't understand why its not a simple to change out battery instead of hardwired. Its my biggest complaint about the garmin GPS's.

George
 
Before you give up on the battery, plug it into the 110v charger overnight. I have to do this once or twice a year when my acquisition time slows down. It is the original battery and was purchased in Summer '07.....
 
flyingriki said:
Before you give up on the battery, plug it into the 110v charger overnight. I have to do this once or twice a year when my acquisition time slows down. It is the original battery and was purchased in Summer '07.....
Click to expand...

another note, the clock battery only charges when the 396 is on. So when you charge it overnight make sure to leave it on.
 
Same symptoms on my 496, called tech support and they will replace the internal battery for $400! No thanks. They did say that the latest firmware update will improve satellite acquisition even with a dead battery, but the only way to get quick lockons consistently (even after exended periods of non use) is to replace the internal battery. I agree with the above post that an overnight AC charge with the unit on greatly improves acquisition times for a while. Also, if I just turn my unit on at least once per week, even with the dead internal battery, I can still get a lock within 1-3 minutes. FYI, there's a couple of YouTube videos out there that outline how to replace the internal battery and a couple of folks who added a bigger battery and a mod to make the battery more replaceable -- not a job for the faint of heart though unless you're handy with small electronics and a precision point soldering iron ... or if you have a spare unit to practice on first!
 
If you don't feel comfortable doing it or don't have the tools I'll replace the battery for you for $50. I even have the battery in stock!
 
I would take Walt up on that deal. Even with shipping costs your way ahead of what Garmin would charge and I suspect Walt knows exactly what he is doing so you don't have to worry about bricking the unit.

George
 
Thanks Walt, I may take you up on that. However, curiosity is getting the better of me so I'll at least have to take a look.

...Is it still $50 bucks if I send you a box of random parts? :D

The one thing I'm not getting out of this is the need to charge the battery as an aid to lockup. Is this internal battery a rechargable type? My unit is always powered on when I fly, and the main battery always shows a full charge... How does frequency of use help keep this alive?
 
The internal battery is a Lithium rechargable type, but like all rechargable batteries they eventually won't hold a charge.
 
Lithium rechargables can't take being completely discharged. It will kill em fast.

The poor design of the x96 does not charge the backup battery unless it is turned on.

This means if you charge your unit with it turned off, the battery will eventually go dead.

Also infrequent use and or only using it for short periods will kill it. The infrequent one is obvious but the short duration one will also kill it because it takes a long time for the battery to charge back up during use. Short periods of use never get it charged.

If you use your unit a bunch and/or keep it turned on when charging (you can turn the backlight off), the backup battery will last a very long time.

The charge level of the main battery has nothing to do with the backup battery.

If the backup battery dies, the unit will lose its time and if it does that, it will be trying to lock onto the sats with the incorrect almanac info and this will cause the long wait for a signal lock.
 
Last edited:
Also, when you turn on the unit on, press the power and out button simutaneously until the I Agree screen appears. This forces the unit
to search for satellites. As mentioned previously however, charging the
unit overnight with the AC power cord works best.
 
Toobuilder said:
So how does the 196, with its dry cell main battery (and no charger) work so well?
Click to expand...

Good question. Must be made different inside. It might not have a backup battery. It may use the dry cells with a capacitor backup for the time you are changing the batteries.

Try taking the main cells out and leave it overnight and see if it loses it's time.
 
My 396 clock battery started going bad about three
years ago. I considered replacing it, but then Garmin
came out with a software rev. that invoked 'Autolocate'
without doing the ' forced autolocate'
(power + out button) turn on procedure.
Because of RV speeds, I only average about one hour
a week and have 'sat lock-in' by the time I taxi to
the end of our 5000' runway, (about 5 min.). This is
with my dead original clock battery. My 396 is powered
by A/C power, (through the master switch) and the
main GPS battery is only for backup.

At turn on, my GPS clock shows time a few hours after
my last flight. This date/time can be two or three weeks old.
I just check that it is in 'Autolocate'.

So far, I'm just ignoring the problem,
Tom
 
Last edited:
Before you start replacing things try updating your 396 code. A friend of mine has a 396 and it could not find the satellites - he tried everything including changing att. It started out intermittent and finally got where it didn't find anything. We logged on to Garmin and updated the code (Not the Nav data) and it started working right away. His code was several years old so the update fixed it.
 
Brantel said:
Lithium rechargables can't take being completely discharged. It will kill em fast.

The poor design of the x96 does not charge the backup battery unless it is turned on.

This means if you charge your unit with it turned off, the battery will eventually go dead.

Also infrequent use and or only using it for short periods will kill it. The infrequent one is obvious but the short duration one will also kill it because it takes a long time for the battery to charge back up during use. Short periods of use never get it charged.

If you use your unit a bunch and/or keep it turned on when charging (you can turn the backlight off), the backup battery will last a very long time.

The charge level of the main battery has nothing to do with the backup battery...
Click to expand...



OK, the unit is panel mounted in the airplane and is flown often enough to keep the main battery topped off, but it sounds like this may not be enough to keep the clock battery happy. Is there some kind of a "maintenance charge" schedule that I should do to make sure the little battery stays up? Perhaps take it out of the airplane once a month and let it cook on wall power overnight?

It makes sense that I killed this battery - this unit sat in a box for many months while I was rewiring the airplane. Now that I know better, I'll pay more attention.
 
After I changed my battery, I would charge it overnight with the unit turned on but with the backlight turned off. I would do this about once a month. Worked great.....


Toobuilder said:
OK, the unit is panel mounted in the airplane and is flown often enough to keep the main battery topped off, but it sounds like this may not be enough to keep the clock battery happy. Is there some kind of a "maintenance charge" schedule that I should do to make sure the little battery stays up? Perhaps take it out of the airplane once a month and let it cook on wall power overnight?

It makes sense that I killed this battery - this unit sat in a box for many months while I was rewiring the airplane. Now that I know better, I'll pay more attention.
Click to expand...
 
I had the same problems with my 396 as the OP..

After reading the thread I did a search and found a site that showed how to replace the internal battery, and where to purchase them. They are $2.68 at Digikey, but cannot be shipped USPS because they are hazardous, so have to go UPS to the tune of $12. A battery that is about 1/4" in diameter and 3/32" thick, hazardous?? :confused: So, I ordered three to make the shipping more palatable...

Anyway, they arrived and I took my time and in 20 minutes had the unit opened, layers removed, battery replaced, and all reassembled. Now the unit works perfectly. The clock is correct, it remembers my last position, and locks on in under a minute.
 
RV-4 said:
Bobby - THANK YOU for the instructions. I'll need them some day. Mine is still cranking along after 6 years and 540 hours of use. Never did leave it on during charge so not sure how accurate that advice was.....
Click to expand...
 
Last edited by a moderator:
OK, surgery complete - recovery looks good. The old battery was showing 0.2 volts, and the new one was 2.87 right out of the package. Unit powered up fine and took about 5 minutes to find itself through the window of the house. I'm going to let it cook all night on the charger and hopefully I'm good to go.

Thanks for all the advice!
 
Toobuilder said:
OK, surgery complete - recovery looks good. The old battery was showing 0.2 volts, and the new one was 2.87 right out of the package. Unit powered up fine and took about 5 minutes to find itself through the window of the house. I'm going to let it cook all night on the charger and hopefully I'm good to go.

Thanks for all the advice!
Click to expand...

Remember to leave the unit turned on!!
 
Thank you

mikehoover said:
Here is my blog post on replacing the battery:

http://aclog.com/blog/2011/07/22/replacing-the-garmin-gps-496-internal-battery/

I learned from the link on bhester's post above before I changed my battery.

If you can build an airplane, this is a no-brainer, and an entertaining diversion.
Click to expand...

Thanks Mike, I used your info and replaced my battery. I would re-emphasize that a very thin solder tip is required. After I replaced the battery I could not set the date(actually is all you set is the year) until the unit had time to charge the battery by being left ON while plugged into the wall. Thanks again, my 396 is back to normal.
 
Interesting thing

My Dad?s internal battery on his 396 went dead and it would not find itself or it took a long time and he had to go through the method to tell it to find itself. Garmin swore that the battery being dead would not affect the unit finding itself, Dad replaced his battery and it has been fine ever since, Garmin must be wrong. However my battery has been dead for a year+ and it still finds itself just fine, the time and date will be off tell it finds itself and it takes about 3 minutes but that?s less than it takes for a run-up and taxi. So what?s the difference, some will still work and some won?t? It?s a rhetorical question, there may be no answer:confused:
 
It will work but the farther off the date and time is, the longer it will take for it to find itself. If you fly frequently, the time and date may not be getting to far outta whack.
 
Brantel said:
It will work but the farther off the date and time is, the longer it will take for it to find itself. If you fly frequently, the time and date may not be getting to far outta whack.
Click to expand...
Ok My prop is at the shop for at least 3 weeks+, we'll see how it locks on when I fly next. I will report back.
 
Garmin 195 Can't find sats either

Understand the 396 has a clock battery that will run down. Does the old 195 have the same problem ? I gave my "not used in years" 195 to a senior fellow so he could find his way back home in his slick & fast RV-9. He goes out flying like a shot, not paying much attention where he's going having too much fun then when he turns around he's lost track. Really NEEDS a GPS and the 195 won't lock up the sats. Who knows and if so who can replace the battery in a 195? Thanks, Bill of Georgia RV-8a N288WP Bluebird
 
You must log in or register to reply here.