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Thread: EF Johnson 5300 questions

  1. #1
    theplague No Longer Registered

    Default EF Johnson 5300 questions

    Im hoping someone here can shed some light on a problem w/ two 5300's I have. On powerup they just display the version number (V3.13.something) and never goto self test, they will power off/on with the button on the control head etc. Im curious what causes this and if reflashing the firmware will fix it?

  2. #2
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    Sounds like maybe you have remote head setup where head power bypasses internal fusing vs when it is on-body/dash mounted...

    The 5300 boot cycle is as follows (what you see):
    1) Control Head Power / Backlight
    2) Control Head Firmware display
    3) Radio start signal from CH
    4) Radio boots and shows it's Firmware version
    5) Codeplug Current Zone Name
    6) Beep! Channel Name
    ... Radio is now booted

    What you are experiencing is the control head getting power, showing it's internal firmware version the issuing a radio power-up command, but the radio does not wake. This problem usually happens when the main unit does not boot or get power.

    Possible causes:
    -Bad connection between head and radio (external cable or ribbon cable if internal)
    -Blown external or internal fuse
    -Radio was bricked trying to flash the radio (requires JTag flash, likely by the depot)
    -Dead radio

    None of these are a very appealing thing to fix, so I hope it's the former rather than the latter.

    Best luck.

  3. #3
    theplague No Longer Registered


    I got them to boot up to "Cycle Powr" Can you shed any light on what that means?

  4. #4
    Alpha's Avatar
    Alpha is offline T S - Moderator
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    According to the 5100 Service manual (I know it's the mobile not the portable) it sheds some light on the error message:

    "This error message appears when there is a communication failure between the DSP and the back end ADC on the RF deck."

    If the same reason applies, it sounds like the radio may have serious problems. Generally, it means there was some fatal error, and your only option is to turn it off.