Troubleshooting

Systematic troubleshooting is the key to getting back in the air quickly. This guide covers the most common problems and how to diagnose them.

Drone Won’t Arm

The most common beginner problem. Betaflight has safety checks that prevent arming — check the CLI for the reason.

In the Betaflight CLI tab, type:

status

Look for Arming disable flags: and address each flag listed:

Flag	Cause	Fix
RXLOSS	No receiver signal	Verify RX is bound and connected. Check UART config in Ports tab.
THROTTLE	Throttle not at zero	Push throttle stick all the way down
MSP	Betaflight Configurator is open	Disconnect Betaflight Configurator and arm with radio only
ANGLE	Drone not level during gyro calibration	Set drone on flat surface, wait for gyro cal
NOPREARM	Pre-arm switch required	Toggle pre-arm switch if configured
FAILSAFE	Failsafe is active	Check receiver connection
BAD_RX_RECOVERY	Receiver recovered from failsafe	Disarm, wait a moment, try again

Quad Flips or Spins on Takeoff

Immediate flip or spin at liftoff is almost always a motor/prop configuration problem.

Diagnosis checklist:

1. Motor order: Open Motors tab (props off). Slide up Motor 1 — verify the rear-right motor spins. Repeat for 2, 3, 4. Compare positions against Betaflight’s motor diagram.
2. Motor direction: Each motor must spin the correct direction. Compare against Betaflight’s diagram (Props Out = front-right motor spins CCW, etc.)
3. Props: Verify each prop is installed on the correct motor (CW prop on CW motor, CCW on CCW). Also check the prop is right-side up — the curved leading edge should face the direction of rotation.
4. Betaflight motor direction setting: In Configuration tab, verify “Motor direction is reversed” matches your physical setup.

Rule of thumb: If the drone flips toward a specific corner, the motor at that corner is likely incorrect.

No FPV Video / Static

Step 1 — Check antenna: Is the VTX antenna connected? A VTX powered without antenna can be damaged. Also check the goggle antennas are securely seated.

Step 2 — Verify channel match: VTX and goggles must be on the same channel. Analog: use the goggles’ auto-scan feature. Check VTX is powered (LEDs on, or VTX is hot/warm).

Step 3 — Check VTX power: Verify the VTX is receiving voltage. Use a multimeter on the VTX power pads. Check your FC’s VTX pad voltage.

Step 4 — Try a different channel: Interference from other sources can blank a channel. Move to a different channel/band.

Step 5 — Check wiring (analog): Camera video wire goes to VTX video-in. VTX video-out goes to goggles (only relevant if using an external receiver with RCA cables).

Video Has Lines or Noise (Analog)

Horizontal rolling lines or noise in the analog video feed is almost always an electrical noise problem.

Common causes and fixes:

Symptom	Cause	Fix
Thick rolling lines	Ground loop	Ensure FC and VTX share common ground
Thin lines that change with throttle	Motor/ESC noise	Add capacitor on battery pads; add LC filter on camera power
Static noise that varies	Power supply noise	Filter camera/VTX power separately from main electronics
Lines only at high throttle	Voltage sag	Better battery, more capacitance on input

Standard fix: Add a 1000µF capacitor across the battery pads (if not already present) and an LC filter (ferrite + capacitor) on the camera power wire.

Oscillations / Propwash

High-frequency oscillations (during flight, visible as “zippiness”):

• P gain too high → lower P in Betaflight PID tuning
• Insufficient filtering → check filter settings in the Filtering tab

Propwash (wobble when descending after throttle chop):

• D gain too low → raise D-term
• No RPM filtering → enable Bidirectional DShot and RPM filtering (requires BLHeli_32 or Bluejay ESCs)
• Props-in motor direction → switch to Props-Out (Betaflight default)

Slow oscillations (hunting/bobbing in steady flight):

• I-term too high → lower I on the offending axis

Motors Feel Hot After Flight

Some warmth is normal. Too-hot-to-touch after a 3-minute flight indicates a problem.

Cause	Fix
D-term too high	Lower D or enable RPM filtering to allow lower D
PWM frequency too high for ESC	Lower ESC PWM frequency in BLHeli (24kHz default)
Motor bearings worn	Replace motor
Bent motor shaft causing imbalance	Replace motor
Props too aggressive (high pitch)	Try lower-pitch props
Flying at maximum throttle constantly	Normal for racing; consider higher-rated ESC/motor combo

One Motor Not Spinning

1. Swap the motor to a different ESC output (desolder and move the 3 wires to another motor pad). If the motor now works, the ESC pad is bad.
2. Try a known-good motor on the suspect ESC output. If it also doesn’t spin, the ESC output is damaged.
3. Check solder joints on the motor wires — reflow with flux if any look cold or cracked.
4. Check for physical motor damage — spin by hand, listen for grinding, check for bent shaft.
5. Check Betaflight Motors tab — can you spin the motor from software? If yes, the issue is in the arming/configuration, not the hardware.

GPS Issues

No GPS lock:

• Wait longer in an open outdoor area — first lock can take 2-5 minutes
• Check GPS is in the open (buildings, cars, and metal block GPS signals)
• Verify GPS is connected and configured in Betaflight (Ports + Configuration tabs)
• Check GPS module power (usually 5V from FC)
• GPS module may need to be mounted away from other electronics (noise affects GPS)

GPS Rescue not activating:

• Check minimum satellite count threshold — Betaflight requires a certain number of satellites before GPS Rescue is available (set in Failsafe tab)
• Verify GPS Rescue is selected as the failsafe action
• Enable sanity checks in GPS Rescue settings

Receiver Signal Loss in Flight

Intermittent losses (brief static/reconnects):

• Antenna routing: move receiver antennas away from FC and ESC
• Antenna position: keep away from carbon fiber frame (it blocks signal)
• Diversity: use a diversity receiver with two antennas at 90° angles
• Interference: other 2.4GHz sources (WiFi, other pilots) — check your flying area

Complete loss at range:

• Transmitter output power — check radio power settings
• Receiver antenna damage (inspect after any crash near the antenna)
• ELRS packet rate — lower rate (250Hz → 150Hz) for more range
• Antenna polarization mismatch — both TX and RX antennas must be same polarization

Betaflight Won’t Connect via USB

Windows: Install correct drivers:

1. Download ImpulseRC Driver Fixer
2. Run with FC connected
3. Let it install the correct driver
4. Try Betaflight Configurator again

Try a different USB cable: Many USB-C cables are charge-only and don’t support data. Use a known data-capable cable.

Put FC in bootloader mode (for flashing): Hold the boot button while plugging in USB.

Mac/Linux: Usually works without drivers. If not, check if the FC appears in System Information (Mac) or lsusb (Linux).

Post-Crash Checklist

After any hard crash:

• Inspect battery — dents, punctures, swelling? If any: ground the pack permanently.
• Check all props — chips, cracks? Replace any damaged props.
• Spin each motor by hand — smooth rotation? Grinding or wobble = damaged bearing or bent shaft.
• Inspect frame arms — flex test each arm. Cracks that aren’t visible may still flex noticeably.
• Check solder joints — visual inspection for any that cracked from impact.
• Test video feed — power up and verify FPV works before next flight.
• Test arm/disarm — make sure controls still work correctly.