What F1 Means
On Bosch French door bottom-freezer refrigerators, F1 in the diagnostic display is the freezer compartment sensor reporting either a disconnection, shown as Lo, or a short, shown as Hi. The repair manual's check is a resistance measurement at connector CN14 on the main board, and the remedy if the sensor reads open or shorted is to replace the freezer compartment sensor itself.
Common Causes of F1
- Freezer compartment sensor failed open or shorted
- Sensor connector unseated at the main board
- Damaged sensor wiring inside the compartment liner
🔧 One Safe Check You Can Try
Check the freezer is not being asked to do the impossible: door closing fully, vents at the back of the compartment not blocked by packed food, and nothing holding the drawer open. Those conditions can mask or mimic a sensor complaint.
⚠ Why You Shouldn't Go Further Than That
- The diagnostic display that shows this code is entered with a specific button sequence and times out by itself, so reading it reliably takes practice.
- The sensor sits inside the freezer liner, and the panels that cover it become brittle at freezer temperatures and crack when levered.
- Bosch's check unplugs a named connector on the main board, which carries several other circuits that are easy to disturb.
- Replacing a sensor that was only unplugged is a wasted part, and the manual's own procedure is designed to tell those apart.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.