Error codes, and what they mean.
A code names what the control detected, not which part failed. On a Sub-Zero Built-In 600-2 the numbered codes are read in Diagnostic Mode, where each shows with “EC” beside it; day to day the display shows only SERVICE, EE, ICE, or 40 or 50 with EC flashing. A Viking VCC3 inverter reports by flashing a light on its board instead, and the Monogram service documentation we hold has no fault-code table for owners. All of it is taken from the makers’ own service documentation, and only for the series we can verify.
How the three makers differ inside, from the same manuals: side by side. What each named part actually does: the parts, in plain words. What the defrost codes are telling you: frost and ice in the freezer.
Look up your code.
Sub-Zero Built-In 600-2 Series: Code Reference
These are the codes a Sub-Zero Built-In 600-2 logs, taken from its service manual. The numbered ones are read in the control’s Diagnostic Mode, where each shows with “EC” beside it; day to day, the display shows only SERVICE, EE, ICE, or 40 or 50 with EC flashing. Each names what the control has detected rather than what has failed: a thermistor code says the reading coming back is impossible, which points to the sensor or the wiring to it.
- 05 Refrigerator compartment thermistor open, shorted or erratic
- 06 Refrigerator evaporator thermistor
- 07 Freezer compartment thermistor
- 08 Freezer evaporator thermistor
- 20 Defrost under-heat with no voltage feedback at defrost start
- 21 Defrost overheat
- 22 No voltage feedback at defrost start
- 23 Defrost overheat with no voltage feedback
- 24 Defrost under-heat
- 30 Ice maker water valve energized beyond fifteen seconds
- 40 Excessive freezer compressor run
- 50 Excessive refrigerator compressor run
- EE Thermistor at the displayed location is open or shorted
- Sr Showroom Mode: cooling disabled by design, not a fault
Viking VCC3 Inverter: Flash Codes
A Viking VCC3 inverter has no display, so it reports by flashing a light on the board itself. The count is the whole message, and one flash with the compressor running is the healthy state rather than a fault. The board sits behind the upper grille and the control box, so the count is a technician’s reading.
- 1 One flash, compressor running, no fault detected
- 1 One flash, compressor off, no command from the control board, or an open thermistor
- 2 Two flashes, no signal reaching the inverter
- 3 Three flashes, open circuit in the compressor cable or a compressor winding
- 4 Four flashes, compressor or system electrical damage
- 0 No flash, compressor off, no input power, or the inverter has failed
Words on the Display That Are Not Faults
Some of what a display shows is a mode someone set, or the moment after the power comes back. The same two service manuals say what each means.
| On the display | Maker | What it means | What to do |
|---|---|---|---|
| A faint OFF | Sub-Zero 600-2 | The unit was switched off at its UNIT ON/OFF key. The manual warns that 115 volts is still present at the control board | Press UNIT ON/OFF once |
| - - in place of one temperature | Sub-Zero 600-2 | That compartment switched off on purpose, for cleaning or defrosting, while the other keeps cooling | Press UNIT ON/OFF; before serial 2092137, repeat the keys that set it. Then check both setpoints |
| °C | Sub-Zero 600-2 | Temperatures shown in Celsius | Within a minute of switching on, hold the door alarm key and, with it, UNIT ON/OFF for five seconds. UNIT ON/OFF pressed first only switches the unit off |
| Two dashes, for about 30 seconds | Viking VCRB | Power has just been applied; the temperatures follow | Wait |
| SHOW | Viking VCRB | Showroom Mode | Hold ACTIVATE CONTROLS, then HIGHER and ALARM OFF together, until three beeps |
| SAB | Viking VCRB | Sabbath Mode | Hold ACTIVATE CONTROLS and DISPLAY OFF together for three seconds |
| POWER, flashing | Viking VCRB | The power was lost and has come back; no sound goes with it | Press ALARM OFF |
HIGH TEMP and DOOR OPEN are alarms rather than modes: what each beep means. Sabbath Mode on every series: lights out, still cold.
Codes are not universal. The tables above belong to the series named and nothing else. Sub-Zero’s later Classic, Designer and PRO units use different control boards, and other Viking models report differently. Which Sub-Zero series you have. Check the model plate before trusting any code chart you find online, including this one. And a code tells you what the control registered, not what is broken: code 40 can be as simple as a dusty condenser.
Knowing the code is not the same as fixing it.
A code narrows the search. It does not tell you which of four components in that circuit failed, and it does not distinguish a cause from a consequence. A defrost code can appear because a sensor failed weeks earlier, and then replacing the heater fixes nothing.
It is also worth knowing that several of these circuits sit behind panels holding refrigerant lines, and that opening a sealed system legally requires EPA Section 608 certification. The useful thing you can do is write the code down and tell us when you call, so we can bring the likely parts.
Sources
- Sub-Zero Built-In (600-2) Series technical service manual (Job Aid #3758407, 2005): the error code table, Diagnostic Mode and the indicators an owner may see on the display, EE and Sr, and the checks for code 40, the condenser among them; the OFF display (pp. 3-6, 8-9), Celsius (p. 3-16) and a compartment switched off (pp. 3-18, 3-19).
- Viking Preferred Service manual SMR-0022 for the built-in all-refrigerator VCRB5301 / VCRB5361, May 2012: the VCC3 inverter diagnostic codes, and the inverter reached behind the upper grille and the control box; the display at power-up (p. 6), Showroom Mode (p. 8), Sabbath Mode (p. 9) and the power loss indicator (p. 34).
- GE Consumer Home Services technical service guide 31-9091 (2002) for Monogram side-by-side refrigerators ZIS360, ZIS420 and ZIS480: no fault-code table.
Reviewed on (checked again ). Each code belongs to the series named and nothing else. Nothing here is a manufacturer’s instruction.
Read Next
- Find your model numberWhere the model and serial tag sits on all four makers.
- Sub-Zero, Viking, Monogram: side by sideTwelve rows from the service manuals, three built-ins compared.
- After a power outage: keep it, or throw it out?The USDA four-hour rule, and the keep-or-discard chart.
- Refrigerator beeping, and the door looks shutThe door alarm reads a switch, not the door. What each beep means on a Sub-Zero, Viking or Monogram, why silencing fixes nothing, and Sabbath Mode.
Something stopped.
Tell us the code and what happened. We answer every day, 7am–6pm.