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FIOS ONT Power Supply NOT charging battery in BBU

FIOS ONT Power Supply NOT charging battery in BBU

Contributor dpdee13
Posts: 5
Registered: ‎04-01-2009
Message 1 of 10

Started happening after Sandy power outage, after I brought power back on line with generator.


Apparently  I have one of the ONT units that will not function without a good battery.

From what I have gathered it requires at battery in BBU box at all times to make the ONT happy.


Ran over to Home Depot, purchase suitable replacement battery, load in box.


All is well, running home on 10,000 watt generator.


Approx. 4 hours later, no FIOS TV, no Internet, status lights (3) on router indicate power, wireless and coax.

Battery was dated Sept 2011, didn't test before install. Suspect battery may have been weak for the beginning


OK, have been through this before, throw battery on trickle charger (1 amp), run over to HD looking for a newer battery.


Return home, install newer battery, all is well


Battery on trickle charger reads about 12.65 V


Approx. 4 hours later, repeat no FIOS TV, no internet


Pull battery, test with mulitmeter, 9.6V


Load battery on trickle charger, install recently charged battery

All is well.


Approx. 4 hours later, repeat no FIOS TV, no internet


This has been going on for a few days now.


I have three batteries that I am rotating, getting between 4 to 6 hours per charge.


For some reason the Power supply that powers the BBU and ONT is not putting out charging voltage to

the battery.


Guess I need a Verizon tech to come out and replace the ONT and/or Power Supply BBU.


Original equipment, FIOS has been installed at our place for approx. 5 years.




Contributor rrdaniel2
Posts: 5
Registered: ‎11-05-2012
Message 2 of 10

I believe I've got the same problem.


The BBU has a red light telling me that the battery needs to be replaced.


The ONT is non-functional with the "defective" battery and it is non-functional with the battery disconnected.


I thought that since I'm getting power (which was restored five days ago), the power supply would run my ONT, even without a backup battery, but NOPE.  There is no power to the ONT.  


I cannot get through to Verizon by phone, by chat, through the support website, even when I stay on the phone for an hour at a time or go in circles through various troubleshooting routines on the support website, which sends me to a web page that won't load or a page that tells me to call the support number where no one answers.


I'm sure that the problem is the power unit and backup battery.  But I have not been able to find a replacement backup battery. Or a replacement power unit.  And forget trying to get in touch with Verizon!


Thanks for your post, man.  At least is shows me that my problem is not an isolated one.  There is definitely a glitch with power units and BBUs during sustained power outages.


Good luck getting yours fixed!  Me, I'm probably going to switch to another internet/cable/telephone service provider.

Contributor outspoken
Posts: 3
Registered: ‎11-05-2012
Message 3 of 10

The unit doesn't need a battery. Remove the connecting wire from the battery to the unit, on mine these wires are spliced together. Make it a direct connect instead.


This is the exact replacement for most units: http://www.amazon.com/Genuine-GS-Portalac-Original-Equipment/dp/B007ZHAYL6


Reasonable price. You can get cheaper OEM replicas by companies like UPG - or ebay sellers.


I'm curious to know the exact details on the battery you bought. Also, have you checked if there is current coming from the battery cables in the BBU?

Contributor dpdee13
Posts: 5
Registered: ‎04-01-2009
Message 4 of 10

Been through this with FIOS "tech support" many times.


My version of the ONT box DOES require a charged battery in the BBU box to make the ONT box happy.


Something to do with POST check and system status validation.


Batteries can be had in HD or Lowes in the low voltage lighting section, approx. $25.00.

Rechargeable Gell Cell battery, 12V DC 7.5AH, typically, in their case used to back up emergency lighting and alarm systems.


Basic problem is no charging voltage from BBU to battery in the box. BBU is receiving power from Power Supply, System Status light indicates normal, FIOS TV and Internet function as if normal. ONT box is discharging the battery in the BBU due to lack of charging.


I have a fairly sold background in electrical circuts and circut board design. If it were my equipment I would be willing to dig a little deeper. Happy having Phone, Internet and TV at this time. Will continue RR batteries until Sat. AM.


No power coming down the leads with batt. removed. Could be as simple as a loose connection or bad solder joint in the charging circut.


Could be Power Supply, BBU or even some strange fault in the ONT.


Verizon tech scheduled for 11/10/2012 0800-1200, interested to see what the problem is.




Contributor jmsidhu
Posts: 2
Registered: ‎11-06-2012
Message 5 of 10

We are in same situation (though I have not been doing the battery dance).  40 minutes on hold to get through to tech support this morning.


They said they need to send a tech but that they cannot until 11/9/12. 


Did the ONT or BBU get fried when power was restored or did one of the tree guys cut a line somewhere.  My money is on equipment failure.



(from Mountainside via neighbor's Comcast wifi signal)

Contributor dpdee13
Posts: 5
Registered: ‎04-01-2009
Message 6 of 10

Nothing fried as far as I know.


Equipment has worked as expected, except for lack of charge to the battery in the BBU, since I switched over to generator power after we lost the grid to to Sandy. It may have been 30 minutes or so between lights out and generator power on, I had to attend to some driveway flooding issues before I could get the power on, don't know if there was a surge or spike when the grid went down.


I give VZ lots of credit, FIOS was up in our area throughout the storm. We had trees and electric wires down everywhere. I believe most of their fiber is underground in our area.


As long as I keep a good battery in the BBU, everything works. If I had a smart, battery maintainer trickle charger I would be tempted to patch the charger into a battery on the floor then run jumper leads up to the +/- connections in the BBU. Not sure how many amps/watts the ONT is drawing from the battery, I am guessing about 1 amp per hour. If I could add that much back with a trickle charger/maintainer I might not have to swap batteries at all.


As a side note, I have become very proficient at changing batteries, if I pull the one that is about to fail and swap in a fully charged one in less than about 10 seconds the ONT box stays up, all cable boxes hold their data and the IP info in the router is maintained.


I have been too busy with storm cleanup and work to fool around with this too much. We have FIOS Internet and TV to keep the kids from going through withdrawal.


Hopefully the tech shows up Sat AM.




Contributor rrdaniel2
Posts: 5
Registered: ‎11-05-2012
Message 7 of 10

The problem with my ONT is definitely a problem with recharging the battery.  Got a replacement battery at Radio Shack today, put it in and *bingo* we were back in business.  The ONT was happy and booted right up.  But after about 6 hours, the ONT began "flickering" (shutting down, then coming back up, in rapid alternance) as the battery drained.


It is clear that something happened in the storm to the power supply and/or the BBU so that it no longer recharges the backup battery.  And I tried bypassing the battery, but the ONT will *not* work unless a charge battery is connected.


So... I'd have to follow Dave's example by having multiple batteries to swap out, putting the depleted ones on a trickle charger, before swapping them back into the BBU as the service battery depletes its charge.


The question is... what happened?  How did Sandy disrupt the proper functioning of the BBU and ONT?  Why did they work nicely together before Sandy and stop working after Sandy? There was relatively little lighning. But maybe there was some sort of power surge that burned out or damaged a microchip that controls the recharging of the battery in the BBU?  I don't know.  But I sure as heck am not happy with service from Verizon, even though I -- finally -- was able to get through to a rep using Verizon support chat, a rep who promised me a call from a technician tomorrow.


Keeping my fingers crossed.


Good luck to others whose service is out.  I hope you soon find the solutions you need.





Contributor Fishnyc22
Posts: 1
Registered: ‎12-23-2012
Message 8 of 10
Same problem here after sandy. Bought a 2nd batter from Verizon but it drained after 6 hrs or so. Pulled 2 batteries out of an unused UPS and it killed those too. Even hooked up to generator wouldn't charge batteries.

After power was restored it did start charging again.

But this week one of the 2 power lines coming into my house was loosened after a wind storm and my house power was all messed up. Half the circuits were going on and off like crazy. I turned off the breakers that were problems. When the power was fixed the BBU unit stopped charging the batteries.

I've been charging the batteries in my UPS and putting them into the BBU charged but it just drains down to nothing.

Getting annoying and FIOS can't make it till 1/3/13.

Found this thread looking to resolve it myself. Anyway to fix this on our own?

Thanks guys.
Contributor richmcg
Posts: 1
Registered: ‎01-27-2013
Message 9 of 10

I know this is an old thread but...

I experienced the same problem after  I plugged my ONT back in unit. (I had unplugged it to paint the wall.) The Verizon tech replaced my ONT unit. He stated that the ONTs with only two pronged AC plugs- the one I had - are known to fry the BBU due to electrical surges. He replaced it with a three prong electrical plug.

Contributor jvd357
Posts: 1
Registered: ‎02-09-2013
Message 10 of 10

Can you tell me specifically what the best charger would be to recharge my beeping Fios battery? I AM able to remove the battery and not have any interruption to my services. I've read elsewhere that the batteries can be recharged but I would like to know what kind of charger to use.



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