HP Chromebook 11 G1/G2 Repairs

 Log

  • Added information on fixing devices that don't charge.
  • First post, containing charger replacement information.

TLDR

I have tested and recommend the following replacement hardware for charging problems:

    Battery Charge Failures

    If your laptop has discharged to a very low state, it may become unbootable due to the battery not charging. This is seems like an embedded controller failure and is fixed by unplugging the battery cable. Please follow this Youtube tutorial for a visual aid:

    External Charger Compatibility

    HP's Micro USB power supply is one of the common points of failure on this laptop. This is inherent to the design (high amp 5 volts), which is both stressful on the current generating components and the cables. It is not uncommon for original chargers to constantly shut themselves off from overheating.
    To meet the 3A current target, there needs to be a reduction of contact resistance, so the cable is soldered and of very high thickness - can't even be repaired, as the circuits are glued to the casing for safety reasons.

    Charging Diagnostics

    To diagnose current on the Chromebook you need to:
    • Put the device in developer mode.
    • Issue 'emerge ec-utils' on a console (Ctrl+Alt+T).
    • Issue 'ectool powerinfo' on the console.
    This will show you the current and voltage of the charger. It also shows the charger type connected, which can help you diagnose why it may not be supplying higher currents.

    Cable Replacements

    HP signals support for high power chargers through a non-standard resistor on the charger plug, connected to the ID pin. You can ignore the laptop's warning and still charge the device while in use, as long as the charger and cable are compatible. For cables, I tested and recommend:
    • 24 or 22AWG for 1 meter / 3.3ft - around 2.0A @ 5v.
    • 22 or 20AWG for 2 meter / 6.6ft - around 1.5A @ 5v.
    The lower AWG the better (official charger uses 18AWG, which is not very common) and these values are for a charger that compensates voltage drop over the cable. Anything over 2 meters will be very hard to acheive due to physics.
    If you need to connect a Slimport adapter, keep the power input cable as short as possible.

    Charger Replacements

    There are very few USB chargers that can be called compatible with the ARM HP Chromebook 11. Official firmware supports the following high current modes:
    • HP official charger: 3A
    • Slimport adapter: 2A
    • Apple USB chargers
      • 2.4A @ 5.25v - model A1401
      • 2.1A @ 5.10v - model A1357
    • USB Charging Downstream Port: 1.5A standard, but firmware allows higher current.
    • USB Dedicated Charging Port: 1.5A maximum.
    Anything other than this will only charge at 1A maximum, sometimes 0.5A.

    The recommended charger is one of the Apple chargers but you must source one from Apple - counterfeits will be both unsafe and low power. With one of the aforementioned cables, this setup will supply up to 2.4A @ 5.25v, which is usually enough to compensate the voltage drop at full current. It is expensive but also a very high quality device.

    Alternatively, the RAVPower 30W USB Chargers, which feature iSmart 2.0, a voltage drop compensation technology:
    RAVPower 30W 3-Port USB Charger (RP-PC020)
    This charger will auto signal USB DCP, maxing out at 1.5A, but that is usually enough to charge while in use - more is only needed with unpowered USB hubs or other drain sources connected to the laptop.
    This has been a very reliable charger, which I found through the info on the Lygte USB charger reviews of the QC 3.0 version.

    Charging Port Failures

    Over the extent of my ownership of the device, the charger port developed contact resistance and couldn't draw more than 1A from the charger, no matter the cable/charger combination. This is not enough to keep the device going for more than 5 to 6 hours.
    You need to have it replaced on a smartphone repair shop or buy a new USB PCB of eBay. If available, USB boards should cost less than 20eur/$25.
    For replacement, the Micro-AB port can be changed to a regular Micro-B port, which is what most chargers and OTG accessories use. 
    Published

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