Safety first: Remove the battery immediately. Do not continue to power the unit if you suspect a short circuit or smell burning.

Remove all accessories: Detach the wand and all tools. Install only the main body and battery, then briefly test. If E7 clears, the fault is in an accessory.
Test accessories one by one: Attach each motorized tool (e.g., mini motorized brush) individually and test. The accessory that triggers E7 is likely shorted and should be replaced.
Inspect wiring: Check visible wiring in the wand and floor head for cuts or crushed sections.
Check main motor: If E7 appears with no accessories attached, the main motor or PCB is suspect. Inspect for burn marks or melted plastic around the motor area.
Replace faulty module: Replace the defective Motorized Tool, Main Motor Assembly, or Main Control PCB as identified.
Professional service: If you are not comfortable diagnosing electrical shorts, contact an authorized Roborock service center.

Vacuum displays E7; LED indicators flash and motor does not start.

Possible Causes