Thermador PRD366WGU Pro Grand Range F12 Error Fix: Oven Control Board Overvoltage Protection Triggered

Error code F12 on the Thermador PRD366WGU Pro Grand Range means: Oven Control Board Overvoltage Protection Triggered. The oven control board has detected an overvoltage condition, likely caused by power surges or faulty wiring. This safety feature disables oven operation until the issue is resolved to prevent damage.

The most successful fix is "Replace Control Board and Inspect Wiring" (hard difficulty, ~90 minutes). Estimated DIY cost: $0-$0. HomeMD has 2 community-ranked fixes for this error.

This error is rated critical severity. It is generally not urgent and can often be resolved with a simple DIY fix.

Yes — the top-ranked community fix ("Replace Control Board and Inspect Wiring") is rated hard difficulty and takes about 90 minutes. Tools needed: Phillips screwdriver, Multimeter, Nut driver.

DIY cost: $0-$0. Professional repair typically costs $250-$400. Many homeowners save money by trying the top-ranked community fix first.

The Thermador PRD366WGU Pro Grand Range has 8 other known error codes, including: F0 (Electronic Oven Control Failure), F1 (Electronic Oven Control Failure), F10 (Control Board Communication Error), F11 (Oven Temperature Sensor Short Circuit), F13 (Oven High Limit Thermostat Open), and 3 more.

Error code F12 also appears on 5 other Thermador models: MED301JS 30 in Masterpiece Series Single Wall Oven with 4.3 cu ft Capacity and Steam Bake, PODS301W 30 in Wall Oven with 4.3 cu ft Capacity and Convection Cooking, PRD486WDGU Pro Grand 48", PRL366WG 36 in Pro Grand Range with 5 Burners, 22,000 BTU Power Burner, and Convection Oven, T36BT925NS 36 in 20.9 cu ft Freedom® Collection French Door Refrigerator with WiFi Connectivity and ThermaFresh System. The fix may vary by model, so check each model's specific page for tailored repair steps.