Appliance Error CodeDatabase
Verified Bosch Dishwasher code

Bosch Dishwasher E12 error code

Limescale in heating system. Start with safe external checks, then confirm the code against documentation for your exact model.

Manufacturer-source verifiedReviewed 2026-08-23Basic checks first
CodeE12
ApplianceDishwasher
MeaningLimescale in heating system

What this code means

Limescale build-up is affecting the heating system.

Model check: Code meanings and procedures can vary by model family and market. Record the full model number before ordering parts or following a model-specific reset sequence.

Safe checks to start with

  1. Descale the dishwasher using a dishwasher-safe descaling product according to its instructions.
  2. Inspect only user-accessible areas described in the owner manual.
  3. After correcting an obvious external issue, restart the appliance once and see whether the code returns.
  4. If you see smoke, arcing, a burning smell, active leaking, gas odour or uncontrolled heating, stop using the appliance and isolate the relevant utility if safe.
Report a problem
AdvertisementAdSense-ready placementLoads only after publisher/CMP configuration.

DIY or technician?

Basic external checks only; use the exact model manual before removing panels or testing electrical components.

Repair-cost band: lower/variable. Actual cost depends on model, parts, access, labour and region. See the repair cost guide before booking work.

Related codes and symptoms

Bosch Dishwasher E09Internal dishwasher faultBosch Dishwasher E14Filling/water inflow faultBosch Dishwasher E15Water in base / leak protection activeBosch Dishwasher E16Filling/water inflow faultBosch Dishwasher E19Dispenser or internal valve faultBosch Dishwasher E22Filters blocked
Primary verification source: Bosch Support. Last reviewed 2026-08-23. This independent summary is not a substitute for the exact model manual.