zero volts on V-Batt 1 after upgrade from 10.4 to 12.4

  • Hello Richard,

    I upgraded my Royal SRS from 10.4 to 12.4 last night, and I'm now seeing zero volts on the V-batt 1. I tried swapping the batteries from socket batt2 to socket batt-1 and vice versa but it doesn't make a difference, zero volts on V-batt 1 on telemetry and on the screen. Any thoughts on what could be going on? Have you seen this before? Should I try to downgrade the unit?

    I hope to hear back soon, thanks in advance for your support.


  • Richard,

    I understand what you mean about this not being a typical error, I have several Royals & have been running some of them for years, and have never seen this before either. The unit shows a value on I-out, V-out A and V-out B, when I disconnect either battery the unit continues to operate. The only issue is the left side battery voltage display shows 0.0, the right side shows a voltage. When I swap the batteries between sockets, it shows the new batteries voltage on the right, the left side is still 0.0 volts. Also, the bar graph is not filled in on the left side, the right side shows output and min value. If I go to the Power-Flight Recorder screen Batt 1 shows a low number for the min voltage and max current values, there is also minimal consumption increments, like 1 mAh every min or so, the right side shows correct values for Batt2. Batt 2 seems to be the only battery being used by the unit for some reason. thoughts?

  • ok, I was hoping this wasn't the case, the PB is built into the model and will be a lot of work to remove. It is also late in the season, I bought the unit from Gerhard, would it be acceptable to send this unit to him and have him send me a replacement? It's less than a year old. I hope you find that acceptable. LMK.


  • Hello,
    I´m sorry- we cannot replace in advance, because we have no usage for your used PowerBox. I´m sure it´s only a little defective. I think this is not a critical error, so use it to the end of season. You can talk with Gerhard- he willservice it to us.

  • Hi Richard,

    I'm sorry, I don't think I was clear, I am not requesting a advance replacement. What I was asking is if it could be replaced by Gerhard when I send him this unit instead of waiting for the unit to be sent to Germany. I don't feel comfortable flying the plane if the PB is malfunctioning, the model is very expensive. LMK.

  • Ok, I removed the unit tonight and will send it to Gerhard tomorrow. One additional question, why do some of my units upgrade to 12.3 and some to 12.4? What is the difference between the two versions?

  • ok, the one I shipped to Gerhard is 12.4, I have an other Royal in an other jet which I just upgraded but it shows 12.3 and it appears to be working fine after the upgrade. Do you think xx.4 may have something to do with my issue?


  • Hello,
    no- this has nothing to do with that. If your Tx system is supported with xx.3 all is fine. Newer versions have more different Systems for example Jeti UDI or JR Dmss

  • I just wanted to let you know that I had a similar problem with mine. One battery would turn on and the other one would not. it turned out to be the switch connector at the power box that was not all the way in. Vibration loosened it and when I pushed it in fully it worked. I used double stick tape on the power box mount to keep this from happening. Thankfully if it happens in flight the battery will remain fail by remaining on.

  • Hello cespedes,

    I received your unit and checked it. I found a burned diode and a burned conductor track. Typically this happens, when power is connected to the servo-outputs.
    Please check your setup if it is possible that there was power connected to the servo-sockets.
    Nothing to worry by the way, this can be repaired and is not a big thing.