Troubleshooting

Step-by-step fixes.

Common issues, diagnosed from first principles. If you've gone through these steps and something still isn't right, we're on Discord and email.

Unit won't power on
  1. 1Confirm the battery is not fully depleted - connect AC and wait 60 seconds before pressing power.
  2. 2Hold the power button for 3 full seconds. A brief press only activates standby.
  3. 3Check the internal fuse (rear panel, single M3 screw). If blown, replace with a 30 A ATO blade fuse.
  4. 4If the display flickers and dies, the BMS may have tripped on an over-discharge condition. Leave on charge for 2 hours and retry.
AC outlets have no output
  1. 1On the touchscreen, confirm the AC rail is enabled - tap the AC button to toggle it on (LED should be amber).
  2. 2Check that you're not in ECO mode with no load - ECO mode disables AC until draw exceeds 3 W.
  3. 3Verify the unit is above 5% battery state of charge - AC output is disabled below this threshold.
  4. 4If a large surge load caused a trip, the inverter will auto-reset after 30 seconds. Try again.
USB-C won't fast-charge my device
  1. 1Confirm you're using a USB-C cable rated for 5 A (20 V × 5 A = 100 W+). Cheap cables cap at 3 A.
  2. 2PD negotiation can take 2–3 seconds after plug-in before switching to high wattage.
  3. 3Some older devices don't support PD 3.0 - they'll charge at 5 V / 3 A regardless.
  4. 4Check the touchscreen: the USB-C live watt reading will show what's actually being drawn.
Fan is louder than expected
  1. 1Confirm the unit is not in a high-ambient environment. At > 35 °C ambient, fans will run faster.
  2. 2Check the air path: intake (left side) and exhaust (rear) must not be blocked.
  3. 3If the noise is a rattle rather than airflow noise, a fan blade may have debris on it - swap is straightforward (see mod guide).
  4. 4ECO mode runs fans at minimum speed. Enable ECO via the touchscreen if noise is a priority over performance.
Capacity reads lower than rated
  1. 1State of charge estimation is calibrated over full charge-discharge cycles. New units can read slightly low for the first 5–10 cycles.
  2. 2Run one full charge (to 100%) followed by a full discharge (to auto-shutoff) to recalibrate the coulomb counter.
  3. 3Capacity at cold temperatures (< 5 °C) will appear lower - this is normal. Capacity recovers at room temp.
  4. 4If capacity has dropped below 80% after fewer than 1,000 cycles, this is covered under warranty.
Touchscreen is unresponsive or shows garbled display
  1. 1Hold the power button for 10 seconds to force a hard reset.
  2. 2If the issue persists after reboot, check the display ribbon cable at the board (rear panel access, 4× M3 screws).
  3. 3A firmware update may be available - check the changelog at voltpak.com/support/manuals.
  4. 4If hard reset and cable check don't resolve it, contact support for a warranty replacement.
Expansion battery not recognised
  1. 1Power off the host station before connecting or disconnecting the expansion battery.
  2. 2Press the SB50 connector firmly until it clicks - a partial seat will prevent BMS communication.
  3. 3After connecting, boot the station and wait 10 seconds. The display should show combined capacity.
  4. 4If still not recognised, check the BMS UART passthrough connection on the expansion battery side (see technical manual for connector pinout).
Still stuck?

Post in the Discord #support channel - someone who's already dug into their VoltPak probably has the answer. Or email us and we'll work through it together.