A Lua script has to allow arming, and has not

What ArduPilot says:

• PreArm: Too many auxiliary authorisers
• PreArm: Auxiliary authorisation refused
• PreArm: memory low for auxiliary authorisation
• PreArm: Waiting for auxiliary authorisation

A Lua script can register itself as an extra authority for arming; ArduPilot then arms only after every such script has said yes. “Waiting…” means a script registered and has not answered yet. “…refused” means it said no and gave no reason (when it gives one, you see that text instead). “Too many auxiliary authorisers” means more than 3 scripts registered. “memory low…” means there was no memory for the script's answer.

What to do, most likely first

1. The script is still starting, or its condition is not met yet.

   CheckThe Lua Applet Catalog explains the applets that ship with ArduPilot; the scripts on your SD card are in APM/scripts.

   FixWait some seconds after start-up; then read the script's own description for what it wants before it allows arming.

2. The script stopped with an error after registering, so it will never answer.

   CheckLook for a “Lua: …” error line earlier in the messages.

   FixFix or remove the script and reboot.

3. More than 3 scripts ask to authorise arming, or scripting has run out of memory.

   FixRemove the scripts you do not need; raise SCR_HEAP_SIZE if the board has memory to spare. Reboot.

Parameters to look at

Where to do it:Lua Applet Catalog