Model reference

Sub-Zero I648PRO

Name: Sub-Zero I648PRO
Brand: Sub-Zero

Refrigerator

4 documents34 error codes17 service modes

Available documentation

Service Manual

Sub-Zero Revision 1: Prior to Serial 3559999 — Service Manual97 pg
Covers this model
Sub-Zero Revision Hydrocarbon (7041201): After Serial 3560000 — Service Manual88 pg
Covers this model

Parts Manual

Sub-Zero Revision Hydrocarbon (7041202): After Serial 3560000 — Parts Manual9 pg
Covers this model
Sub-Zero Revision 1 (7004859): Prior to Serial 3559999 — Parts Manual8 pg
Covers this model

MyPros+ Max

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M+ Max·Sub-Zero Refrigerator

01 on my Sub-Zero I648PRO

M+

Zone cabinet thermistor failure (device

From Service Manual 852889, p.21:

1.Access service mode to confirm the active fault code and read stored error history.

2.Disconnect the sensor and measure resistance. Expected: 10 kΩ to 12 kΩ at 77°F (25°C).

3.Check the sensor harness for opens. A reading outside 5 kΩ to 50 kΩ indicates a failed sensor.

Part WP8577274

Temperature thermistor

Error codes (34)

CodeMeaning

01Zone cabinet thermistor failure (device or wiring).02Zone evaporator thermistor failure (device or wiring).03Zone condenser thermistor failure (device or wiring).04Ambient thermistor failure (device or wiring).20Check zone defrost bi-metal for proper operation.21Check zone defrost bi-metal for proper operation.22Check zone defrost wiring.23Check zone defrost wiring.24Check zone defrost heater ohms.30Check for stuck icemaker or water valve failure.35Zone fan speed error.40Zone excessive compressor run time.41Check zone compressor and wiring.42Check condenser fan and/or wiring.43Check left refrigerant valve and wiring.44Check zone glass door heater and wiring.45Errors detectable with red door switches are disabled; check overhead lighting.46Check ice accessory wiring for open circuit.47Check accent lighting wiring for short circuit.80Check power to compressor controller for zone; troubleshoot with manual…83Replace zone variable speed compressor and filter-drier.84Check zone variable speed compressor wiring.85Zone variable speed compressor control overheat.86Check communication wiring, replace zone variable speed controller.87Check for broken wiring or open defrost heater.89Check icemaker solenoid valve and wiring.90Change main control board.91Lighting system failure; check bulbs and wiring.92Check keypad wiring.93Replace keypad.

View all 34 error codes

94Check wiring / replace user display (#1 for Zone 1, #2 for Zone 3).96Datalogger malfunction.97Check communications cables / connectors.98Brownout

Service modes (17)

Diagnostics - Activate ZoneAfter initiating Service Mode, press ALARM once, press COLDER three times, press ALARM
Diagnostics - Clear Error History1) Initiate Service Mode
Diagnostics - Error HistoryAfter initiating Service Mode, press ALARM once, press COLDER once, press ALARM two times
Diagnostics - Self TestAfter initiating Service Mode, press ALARM key 3 consecutive times
Diagnostics - StatisticsAfter initiating Service Mode, press ALARM once, press COLDER four times, press ALARM.
Diagnostics - Thermistor ReadAfter initiating Service Mode, press ALARM once, press COLDER two times, press ALARM
Manual Freezer Evaporator DefrostPress and hold the ICE MAKER key for 5 seconds.
Manual Zone Disable ModeWith unit ON, press and hold the WARMER key for the zone being disabled, then press the POWER key…
Model InformationAfter initiating Service Mode, press COLDER two times, then press ALARM two times
Operational Status - Ice MakerAfter initiating Service Mode, press COLDER once, press COLDER once more, press ALARM once
Operational Status - Zone StatusAfter initiating Service Mode, press COLDER once, then press ALARM twice
Sabbath ModeSwitch unit OFF using POWER key
Service ModePress and hold any COLDER key, then press the POWER key, then release both keys.
Service Mode (Diagnostic)Press and hold any COLDER key, then press the POWER key, then release both keys
Showroom ModeSwitch unit OFF using POWER key
Temperature Units Selection ModeMust be done within the first 1 minute after switching unit ON
Version InformationAfter initiating Service Mode, press COLDER three times, then press ALARM once

Full entry steps, exit procedures, and test sequences are available in Max.

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