mypros+
Error code reference

Sub-Zero Refrigerator Error Code 35 3 00

Zone 3 evaporator fan open circuit detected.

Sub-Zero codesSub-Zero refrigerator codes

Zone 3 evaporator fan open circuit detected.

First step from the service manual

Check control board and fan.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

MyPros+ Max

Get the full diagnostic procedure for 35 3 00.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

What 35 3 00 means on a Sub-Zero refrigerator

Error code 35 3 00 on a Sub-Zero refrigerator indicates that the control board has detected an open circuit condition in the Zone 3 evaporator fan circuit. An open circuit means the electrical path between the control board and the fan motor has been interrupted, preventing current from flowing. Zone 3 refers to a specific cooling zone within the unit, and its evaporator fan is responsible for circulating air across the evaporator coil and distributing cold air through that zone. Without this fan operating, the affected zone will lose its ability to maintain proper temperature.

The open circuit can originate at several points in the fan circuit. The fan motor winding itself may have failed internally, breaking the circuit. Wiring between the control board and the fan connector may be damaged, corroded, or have a loose terminal that has separated under vibration or thermal cycling. The fan blade may be physically obstructed, causing the motor to stall, overheat, and burn open. Diagnosing this code requires checking continuity through the fan motor windings, inspecting all wiring harnesses and connectors along the circuit path, and verifying that the control board is sending the correct supply voltage to the fan. If voltage is present at the fan connector but the fan does not run and shows no continuity, the motor itself is the likely failure point.

Source: manufacturer service documentation.

Common causes of 35 3 00

  1. 01

    Failed evaporator fan motor

    Part replacement

    The fan motor winding can burn open internally, creating an open circuit. Checking continuity across the motor terminals with a multimeter will confirm this failure if no continuity is present.

  2. 02

    Loose or disconnected wiring connector

    Wiring / connection

    Vibration and thermal cycling can cause the harness connector at the fan motor or at the control board to loosen or separate entirely. Visually inspect all connectors in the Zone 3 fan circuit for proper seating and signs of corrosion.

  3. 03

    Damaged wiring harness

    Part replacement

    The wire harness running to the Zone 3 fan can develop breaks or chafed insulation, particularly where it passes through cabinet panels or near moving components. A continuity test along the harness will identify any break in the conductor.

  4. 04

    Fan blade obstruction causing motor burnout

    Part replacement

    Ice buildup or a foreign object can jam the fan blade, causing the motor to overheat and fail open. Inspect the fan blade for free rotation and check the evaporator area for excessive frost accumulation.

  5. 05

    Faulty control board

    Part replacement

    If the control board output circuit for Zone 3 fan has failed, it may incorrectly detect or cause an open circuit condition. This is less common and should be considered only after the fan motor and wiring have been ruled out.

See the test procedure for each cause

Frequently asked questions about 35 3 00

What does 35 3 00 mean on a Sub-Zero refrigerator?
Error code 35 3 00 means the control board has detected an open circuit in the Zone 3 evaporator fan circuit. This indicates that the electrical path to the fan motor in that cooling zone has been interrupted. The fan cannot run under this condition, which will affect temperature performance in Zone 3. Diagnosis should begin with inspecting the control board output and the fan itself.
Can I fix error code 35 3 00 myself?
Some causes, such as a loose wiring connector, can be addressed by a knowledgeable DIYer with basic electrical skills and a multimeter. However, if the fan motor or control board needs replacement, the repair requires disassembly of refrigerator panels and working with low-voltage control circuits, which is better suited to a qualified appliance technician. Attempting repairs without proper tools or experience risks further damage to the unit.
Is it safe to keep using my Sub-Zero refrigerator with error code 35 3 00?
Continued use with this error active means Zone 3 is not receiving proper airflow, which will cause food stored in that area to be inadequately cooled. This creates a food safety risk if temperatures rise above safe storage levels. It is advisable to check the temperature in the affected zone and move perishable items if the zone is not maintaining proper cooling until the repair is completed.
How much does it cost to repair error code 35 3 00 on a Sub-Zero refrigerator?
Repair costs vary depending on the root cause. A replacement evaporator fan motor for a Sub-Zero unit typically falls in the range of $50 to $200 for the part alone, while a control board can range from $200 to $600 or more. Adding labor from a certified technician, total repair costs generally range from $150 to $800 depending on what components need to be replaced and the complexity of access in your specific model.
Will resetting my Sub-Zero refrigerator clear error code 35 3 00?
A reset may temporarily clear the error code from the display, but the code will return if the underlying open circuit condition in the Zone 3 fan circuit has not been corrected. Resetting without repairing the fault does not restore normal fan operation. The open circuit must be identified and repaired before the error will clear permanently.

Related Sub-Zero refrigerator codes

All Sub-Zero refrigerator codes
View all 296 Sub-Zero refrigerator codes

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass