Erratic Cellular Network Behavior (FP1U)


has anyone seen this? My FP1U has started behaving weirdly just now. It has serious cellular networks problems, with the network unavailable after 1 call or SMS. These are the symptoms:

  • network unavailable to send/receive call/SMS after one or two calls/SMSs
  • no indication of network problem (reception bars full blue at top)
  • affected: call, SMS, 3G
  • wifi not affected
  • bluetooth probably not affected (can’t tell really: FP says pairing with Mac succeeded, Mac thinks differently)
  • not a SIM-card problem: SIM works in other phone, other SIM in my phone same issue, this time with indication of network problem (reception bars red)
  • I can see the name of my operator and I have full reception
  • problem frequently (but not always) goes away by switching off SIM and switching on again, after which I can call 1 number (sometimes 2) or send 1 or 2 SMS
  • Here is some possibly weird fields in the ##4636## phone information (not an expert, they just stand out to me):
    • cell info: (blank)
    • GSM-service: in use / GPRS-service: connection lost
  • Fairphone Kola Nut 1.8.7
  • Build W20-HL.V0035

My personal guess is, after dropping it occasionally over its 1.5 year lifetime the cellular chip and/or antenna is broken. If I’m correct this is located on the daughterboard, right? But it is just a guess as I have no diagnostic experience. Does anybody have any idea on how I can diagnose this problem?

Any input is appreciated!



One other observation: the battery seems to drain quickly now

Let me share the info that I have the same problem with my phone (Samsung Galaxy Ace) for a couple days now.
Symptoms for me were:

  • Suddenly no cellular network anymore
  • only emergency calls possible (but full reception)
  • after going into flight mode and back out of flight mode, network was found within seconds (even really good quality) but after some seconds or minutes it would disappear again
  • only erratically


Even though this is the last thing you mentioned checking the battery is the first thing I’d do.

Go here:

and do the spin test and if the battery is not starting to bloat then try the battery software reset. A bloated battery can cause all kinds of problems, not just the obviously battery related ones.

The battery does not seem to be bloated, I’ll do a reset as soon as it has drained completely, although it seems fine now.

However, performing this test leads to another interesting observation. After removing the battery the time reverts to factory time and this is not reset by syncing with the network.

There is a tiny battery on the main board to prevent this from happening, so I guess (parts of) your main board is broken.

Did you contact support yet? I guess you could probably get your phone repaired under warranty.

No, not yet. I figured it’s weekend, I might try this forum first. Did plan on contacting them after soliciting some feedback here.

Thanks for all the input so far

Interesting. The thing is that the network doesn’t disappear. Everything seems to be working, only I get no tone when I dial a number and then it stops without any error. Texting seems to take ages and then I get a delivery failed error. 3G the same, after w hill the app that uses the network gives up and notifies me of network issues.

Have you contacted Samsung with your issue?

Nope. I’m throwing my smartphone out, it’s in very bad condition - FP2 is on its way