Bosch dishwasher code E12: limescale build-up

What it means

Limescale has built up on the heater. Bosch’s fix is to descale the dishwasher.

What to try

Unplug the dishwasher before any step beyond a quick look, and turn the water off before touching hoses.

1. Descale the dishwasher with a dishwasher descaler, following the product’s instructions. Bosch suggests its own descaler.
2. If your dishwasher has a water softener, keep it topped up with dishwasher softening salt.

Call a technician if

Resetting a Bosch dishwasher

Once you’ve fixed the cause, Bosch’s way to cancel the cycle and clear the code is to press and hold Reset (Start on some models) for about 4 seconds. The dishwasher pumps out the water, which takes about a minute; then open the door and press On/Off. For electronic faults, Bosch’s code list says to switch the dishwasher off at its breaker for 30 seconds. If four lights flash and it beeps, Bosch says to press On/Off, switch off the power for at least 2 minutes, then switch it back on; if it happens again, press On/Off, turn off the water, unplug it and call Bosch.

Still stuck?

Dishes not getting clean: full Fix Finder8 checks for any brand, quickest first.

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