Sub-Zero · Refrigerator error code

90 b 80No communication with the baffle (stepper) control

Cross-checked Power off, standard tools

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Related diagnostic guides

Guide · Refrigerator

Known issue: Whirlpool-built side-by-side (2018-2021) dispenser or ice maker dead from broken freezer-door wires

A class action (Costa v. Whirlpool, D. Del.) alleged that wire harnesses running through the freezer door hinge area of side-by-side refrigerators made 2018 to 2021 under the Whirlpool, Maytag, KitchenAid and JennAir brands break from normal door use, killing the dispenser, ice maker or controls, and that the fix often means a whole freezer door. The court granted preliminary approval of a settlement in March 2026; class counsel later reported final approval. Whirlpool denies the claims. Reported benefits include reimbursement, free repair or partial cash, with a past-failure claim deadline of November 2, 2026.

7 steps ~60 minmoderate

Guide · Refrigerator

Field pattern: Sub-Zero built-in warm, running nonstop or service light on (clean the condenser before any sealed-system call)

On Sub-Zero units the condenser sits behind the top grille (or the kickplate on undercounter models) and loads up with dust and pet hair; the service indicator generally means a compressor is running too long to hold temperature. The common wrong turn is quoting a sealed-system repair or a board before the condenser has been properly cleaned, the condenser fan confirmed and the unit given a full day to recover.

7 steps ~45 mineasy

Guide · Refrigerator

Field pattern: new inverter board, compressor still won't run (check signal and compressor electrically, then refer)

The inverter board only drives the compressor when it has line power, a run signal from the main board and a compressor with sound windings. Forum threads describe owners swapping two or more inverter boards before anyone checked the compressor or the signal. The wrong turn is a second board without checking supply, signal, windings and case ground; a bad compressor is sealed-system work and gets referred.

6 steps ~60 minadvanced

More Sub-Zero refrigerator codes

Sub-Zero · Refrigerator

10 1 02

Zone 1 cabinet thermistor unstable

Cross-checked High-voltage / caution

Sub-Zero · Refrigerator

10 2 00

Freezer cabinet thermistor open

Cross-checked

Sub-Zero · Refrigerator

10 2 01

Freezer cabinet thermistor shorted

Cross-checked

Sub-Zero · Refrigerator

10 7 00

Ambient (on control board) thermistor open

Cross-checked

Sub-Zero · Refrigerator

10 7 01

Ambient (on control board) thermistor shorted

Cross-checked

Sub-Zero · Refrigerator

10 7 02

Ambient (on control board) thermistor unstable

Cross-checked