Bosch induction cooktop shows E020 and none of the cooking zones heat.

Safety first: Turn off the breaker and verify no voltage is present at the cooktop junction box before opening any covers.

• Check supply voltage: Use a multimeter (if qualified) to verify correct voltage at the junction box (typically 240V split-phase in North America or 230V single-phase in EU). Incorrect wiring can trigger E020.
• Inspect terminal block: With power off, remove the cooktop and inspect the terminal block for loose screws, burned insulation, or melted plastic. Tighten connections to manufacturer torque specs and replace any damaged block.
• Internal fuse check (advanced): Access the power module and inspect any onboard fuses. Replace only with identical type and rating. If a fuse is blown, investigate for shorted components.
• Replace power module: If supply and wiring are correct and E020 persists, the power module is likely defective and should be replaced as a complete unit.