Toshiba 12 fault code

What it means

Block 00 (indoor PCB). A fault on the indoor board not covered by a more specific code. The manual's action is simply: reset the supply, then replace the board.

Safety: Safe isolation, then TREAT THE DC LINK AS LIVE. The electrolytic capacitors hold a lethal charge after the supply is off. Discharge through a resistor across the + and − terminals (Toshiba specifies approx. 100 Ω 40 W) and confirm with a meter on DC before touching the board. Never short the terminals with a screwdriver.

Source: Toshiba service manual SVM-19001-3 (Seiya) / SVM-20015-4 (Shorai Edge) §11-4, Table 11-4-1

Can it be reset?

The manual's action is simply: reset the supply, then replace the board.

Source: Toshiba service manual SVM-19001-3 (Seiya) / SVM-20015-4 (Shorai Edge) §11-4, Table 11-4-1

UK models this code applies to

Tap yours to open 12 on that machine.

12 on these comes from each model's own manual, which may not match the meaning above — tap yours to read it.

Now the harder half: proving what caused it

12 names a symptom, not a root cause. In the app, the same code opens a guided investigation: what to measure first, the expected values for your exact model, and an honest verdict — including “nothing in this machine is broken” when that's what the readings say.

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