[Mark Piddington]

Hi. Hope someone can help.

I made some changes to the FS-i6 RC unit. Could not remember what I changed it from so I Reset RC unit to factory settings.
I have been through the binding process. the flashing light changed from fast to slow as it should on the receiver on the quad. The RC unit said binding ok.
When I re connected the the battery to the receiver unit on the quad and turned on the RC unit the RX battery indicator does not show up on the RC unit.

[TheOtherCliff]

I'm not sure I understand, but it sounds like the RC receiver is not getting power.

Usually the flight battery power is reduced by the built in BEC inside the ESCs.  That 5V power goes to the FC.  The FC power is directly connected to the RC receiver power with FC traces.

One common issue is that some ESCs don't have a built in BEC.  This type of ESC is usually called "Opto".  Measure the DC voltage across the black and red wires in the ESC servo connector, when a battery is connected to that ESC.  Measure it on the FC pins that those wires connect to also.

Another common issue is to plug your ESC servo connector in backwards into the FC.

[Mark Piddington]

Hi

Thanks for the quick reply. Unfortunately I did not understand half o your message as I am new to programming.

I have attached a PDF that hopefully helps you understand my issue.

Slide 1: Shows binding ok. My RC unit shows the same.

Slide 2: Shows the screen on the RC before you unplug the receiver unit from the battery and bind key. My RC unit shows
            the same.

Slide 3: Shows RC unit screen after battery is plugged back in Receiver unit. My RC unit does not show the same. It still shows screen image on slide 2.

Also when I go through the Remote controller wizard on Libre Pilot it does not communicate.

Thanks Mark

[TheOtherCliff]

Connecting power that way is generally not correct!!!  The reason is that connecting it that way powers the receiver with somewhere between 3.5 and 4.2 volts.  Receivers are generally supposed to be powered by 5 volts.  What is worse is that you have put somewhere between 7.0 and 8.4 volts on an input (the third pin) that is generally only supposed to ever see a maximum of whatever you are powering the receiver with (in your case 3.5 to 4.2 volts).

Only connect that battery "balance connector" during charging (to the charger)!!!!!!!  (Or to a low voltage alarm, but that is another matter.)

For testing purposes, like checking the RC receiver binding, you should generally plug the 3 pin ESC servo connector to the receiver, and plug a flight battery into the two heavy ESC wires.  (The three heavy ESC wires go to the motor if desired, but don't let them touch anything if unconnected.)

When connected fully for flight, the battery (generally 12v or close for typical 3 cell packs) connects to the ESC heavy wire pair and the ESC produces a reduced voltage, 5v on the 3 pin ESC servo connector (small wires).  The 3 pin ESC servo connector is connected to one of the FC's eight, 3 wire servo connectors (8x3 pins poking out of board) and thus gives that 5v power to the FC.  The FC has a tiny 1x8 or 1x10 (etc) plug with wires and more 3 wire servo connectors.  The one of those servo connectors that has 3 wires (the rest only have 1) gives power to the RC receiver.

There is a simple, direct connection inside the FC from power coming in at the 8x3 pins to power going out to the RC receiver via the 1x10 or 1x8 pin connector.