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OEM VERIFIED BENCH
OFFICIAL FAULT CODEd21
FAGOR
FAGOR // OFFICIAL DIAGNOSTIC BENCH

FAGOR d21

Washing MachineElectronic Control Board (PCB) & Bus Communications
Luxury front-loading washing machine in brushed titanium with illuminated dark glass drum
Washing Machine
Other Brands Sharing Code d21:BrandtD21SauterD21OceanD21

Symptom / Description

FAULT

Control board communication error

TELEMETRY // LIVESIG: FAULT_DETECTED

Root Cause

ROOT CAUSE

A communication fault has occurred between the main control board and other components.

CIRCUIT // SUBSYSTEMLOGIC: ROOT_ISOLATED

Repair Instructions

UNLOCKED
1Reset the machine by turning it off at the mains for 5 minutes. If it reoccurs, a service call is needed.
AI diagnostic workshop engine analyzing appliance circuit schematics and error telemetry in real time
AI WORKSHOP PROTOCOL ENGINE
Direct extraction from OEM factory manuals & wiring schematics

Field Actions

DISPATCH
Need Help? Call a Certified TechnicianWorldwide FAGOR Parts Finder
Electrical & Safety Protocol

Always disconnect appliance from 230V/400V mains before opening panels. Use CAT III multimeter for circuit testing.

CALIBRATED BENCH PROTOCOL // CAT III 600V

Workshop Verification & Safety Checklist

WORKSHOP VERIFICATION PROTOCOLElectronic Control Board (PCB) & Bus CommunicationsWashing Machine
2. Multimeter & Electrical Bench Tests (Ω)
MODE: OHMMETER (Ω)AUTO-RANGE
Precision digital multimeter probes measuring electrical resistance in Ohms on an appliance control board
CALIBRATED METROLOGY RESISTANCE BENCH (CAT III)
Nominal Resistance (Ω)
Low-voltage rails: +5.0V DC (Logic), +12.0V DC (Relays), +3.3V DC (MCU). Relay coils: 200Ω–450Ω.NOMINAL
0 Ω (SHORT)CALIBRATED BAND∞ OL (OPEN)
▲ NOMINAL OPERATING WINDOW
Target Component:PCB Power Supply Rails & DC Bus Filter Capacitors
Test Pins & Connections
PROBE (+)
PROBE (-)
Across SMPS output electrolytic capacitors on low-voltage side (test bench verification)
Tolerance & Diagnostic CriteriaDC rail ripple must remain <50mV. Direct continuity (0Ω) across DC bus rails indicates dead short.
1. Pre-Intervention Electrical Safety Protocols
  • !High-Voltage Safety Protocol: Disconnect 230V power before unplugging edge connectors or removing PCB.
  • !High Voltage DC Warning: Wait at least 5 minutes for SMPS and inverter filter capacitors (up to 380V DC) to discharge safely.
  • !Electrostatic Discharge (ESD): Ground yourself to the metal chassis or wear an antistatic wrist strap before touching circuit tracks.
3. Preliminary Mechanical & Visual Checks
  • Inspect PCB tracks with a magnifying glass for blown triacs, darkened copper tracks, or cold solder joints on power relays.
  • Check electrolytic capacitors for bulging tops or leaked electrolyte residue around pins.
  • Verify edge connector locking clips are intact and pins are free of vibration fretting corrosion.
Perform these diagnostic steps before triggering AI Deep Search or replacing boards.Certified Workshop Routine

Frequently Asked Questions: FAGOR D21

FAQ TREE
What does error code D21 mean on a FAGOR appliance?

FAGOR error code D21 indicates: Control board communication error.

What is the root cause of FAGOR error code D21?

The primary root cause for FAGOR code D21 is: A communication fault has occurred between the main control board and other components..

How do I fix or resolve FAGOR error code D21?

To resolve error code D21: Reset the machine by turning it off at the mains for 5 minutes. If it reoccurs, a service call is needed.

Is it safe to clear FAGOR error code D21 by resetting power?

Resetting power (unplugging for 5–10 minutes) clears temporary memory errors. However, if FAGOR code D21 persists, the physical component causing A communication fault has occurred between the main control board and other components. must be inspected or replaced.

How do I test electrical resistance for FAGOR code D21 using a multimeter?

Set a digital multimeter to ohms (Ω). Disconnect power and test PCB Power Supply Rails & DC Bus Filter Capacitors across Across SMPS output electrolytic capacitors on low-voltage side (test bench verification). Expected nominal reading is Low-voltage rails: +5.0V DC (Logic), +12.0V DC (Relays), +3.3V DC (MCU). Relay coils: 200Ω–450Ω.. Tolerance: DC rail ripple must remain <50mV. Direct continuity (0Ω) across DC bus rails indicates dead short..

What safety protocol must be followed before servicing FAGOR code D21?

Standard electrical safety protocol: 1. Disconnect 230V mains power before opening panels. 2. Verify zero voltage at test points. 3. Allow hot water or heating elements to cool below 30°C before handling.

Community Verification

COMMUNITY

Did this solution resolve the issue?

SEMANTIC KNOWLEDGE GRAPH // FAGOR

Related FAGOR Washing Machine Error Codes

Diagnostic Link Mesh14 OEM Cross-References

Cross-referenced diagnostic codes for technicians inspecting similar component subsystems.

E04Water Level Pressure Switch & Air Dome
FAGOR E04: Water level pressure sensor/switch frequency anomaly detected in Washing Machine.
Inspect Protocol
F01Water Inlet Valve, Aquastop & Flowmeter
Water fill timeout exceeded with insufficient water entering the appliance.
Inspect Protocol
F02Drainage System & Drain Pump
Draining problem / Water not emptying
Inspect Protocol
F03NTC Temperature Sensor & Thermistor
FAGOR F03: NTC temperature sensor signal out of range (open or short circuit) in Washing Mac...
Inspect Protocol
F04Door Lock Mechanism & Safety Interlock
FAGOR F04: Door lock safety interlock fault in Washing Machine; door switch contact fails to...
Inspect Protocol
F05NTC Temperature Sensor & Thermistor
Temperature sensor (NTC) error
Inspect Protocol
F06Drive Motor, Inverter & Tachometer Sensor
Motor fault (Tachometer sensor)
Inspect Protocol
F07Drive Motor, Inverter & Tachometer Sensor
Motor control board (Triac) fault
Inspect Protocol
F09Electronic Control Board (PCB) & Bus Communications
FAGOR F09: Operational cycle fault detected during Washing Machine program execution.
Inspect Protocol
d01Water Level Pressure Switch & Air Dome
FAGOR D01: Water inlet / filling timeout in Washing Machine; appliance fails to fill to mini...
Inspect Protocol
d02Drainage System & Drain Pump
FAGOR D02: Water drainage failure detected in Washing Machine; drain pump cannot evacuate wa...
Inspect Protocol
d07Door Lock Mechanism & Safety Interlock
FAGOR D07: Door lock safety interlock fault in Washing Machine; door switch contact fails to...
Inspect Protocol
E1NTC Temperature Sensor & Thermistor
Temperature issue in the refrigerator compartment.
Inspect Protocol
E2NTC Temperature Sensor & Thermistor
FAGOR E2: NTC temperature sensor signal out of range (open or short circuit) in Hob / Cooktop.
Inspect Protocol
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