Sub-Zero Classic BI and Designer Code 10-1-00: open sensor in the refrigerator or Zone 1

What 10-1-00 means

Code 10-1-00 shows up on two Sub-Zero platforms: Classic Built-In units such as the BI-36U/S and BI-36UFD/S, and Designer models like the DET3050CI. On the Classic BI it means the refrigerator cabinet thermistor is open. On Designer it means the Zone 1 thermistor is open. Either way the board has lost the sensor that tells it how cold that space is, so it falls back to estimated run times and the temperature can wander.

Common causes of 10-1-00

A disconnected or loose plug where the thermistor meets the harness
A broken wire between the sensor and the control board
An open refrigerator (BI) or Zone 1 (Designer) thermistor

✓ One safe check you can try

1. Check the displayed refrigerator temperature against a thermometer on a middle shelf. 2. Keep the door closed as much as possible. 3. Turn the breaker off for one minute, then on again. 4. If 10-1-00 returns, move perishables to a cooler and book a visit.

! Why to stop there

The sensor and its plug sit behind interior panels
Telling a broken wire from a dead sensor takes a resistance test
The repair differs between Classic BI and Designer wiring layouts

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

→Same appliance

Other Refrigerator codes

23Sub-Zero 600, 700 and 648PRO Code 23: Defrost overheat with no feedback 50Sub-Zero 600 and 700 Series Code 50: Refrigerator compressor running too long 41Sub-Zero 648PRO Code 41: Zone compressor or wiring problem 81Sub-Zero 700-2 Code 81: Variable-Speed compressor fails to start 82Sub-Zero 700-2 Code 82: VS compressor controller needs replacement 88Sub-Zero 700TF Code 88: Board and compressor controller not talking 80Sub-Zero 700TF Code 80: No inverter feedback after a board change ddSub-Zero 600 and 700 Series Display dd: Diagnostics switched off

10-1-0010-1-00 questions

Does 10-1-00 mean the same thing on every Sub-Zero?

It names the first cooling area on both. On the Classic BI that is the refrigerator cabinet thermistor; on Designer it is the Zone 1 thermistor. In both cases the reading is open, so the board sees no sensor at all.

Will my refrigerator stop cooling with this code?

Usually not right away. The board keeps running on a backup pattern, but it can overcool or undercool. A thermometer on a middle shelf tells you whether food is still in a safe range.

What does the repair involve?

We locate the open point, which may be a plug, a wire or the sensor itself, and fix only that. You get a written price before work and a 30-day workmanship warranty on our labor.