Fault showing on fibre to tbe premises

[Ipmdfm2]

 

Hi

our box shows with a red light under fault, see attached,but everything is working  any ideas what we need to do

[Starwire]

That’s just the BBU, Battery Back Up Unit. Batteries are most likely knackered.

I assume you have a 4+2 or a 1+1 ONT.

The BBU was only ever there as a Back Up for FVA in the event of a Power Cut.

You can plug the power lead directly into the ONT as when the batteries die the ONT will lose power and you’ll lose service.

[Ipmdfm2]

Sorry  what is ONT and FVA and what can we do in simple terms . Our landlines is now digital

[jac_95]

@Ipmdfm2 you can try and replace the batteries as per https://www.bt.com/help/landline/fibre-home-phone-service--questions-about-the-battery-back-up-un

Although this battery backup unit (BBU) was usually only supplied if you had the legacy Openreach voice service called Fibre Voice Access or FVA where you plugged your phone into the Openreach Optical Network Termination (ONT) unit. FVA has been withdrawn and customers are moving to their suppliers digital voice service which is BT digital voice for BT Consumer customers.

You can also unplug the BBU and connect the ONT to the mains or if you need to continue to supply power in a powercut a UPS (Uninterruptible Power Supply) device.

[Starwire]

ONT - Optical Network Termination Point, aka the bigger of the two boxes. Basically a Modem.

FVA - Fibre Voice Access, aka Voice Phone Service Supplied over Fibre Optical Cable.

As you now have Digital Voice you don’t need the BBU, as I said you can plug the mains power supply directly onto the ONT.

[DavidM · Accepted solution]

Hi @Ipmdfm2 and welcome to our community.

Thanks for posting about your ONT. Both @Starwire and @jac_95 advice is perfect. Can you let us know if you're happy with those replies?

Cheers

David