GE Profile Dishwasher F1 / F2 / F3 Codes Decoded

GE Profile dishwashers (PDT, ZDT, CDT series) throw F-series codes that the manual lists but does not explain in detail. Here is the technician decode and the diagnostic flow for each.

F1: temperature sensor (thermistor) fault

The control read a thermistor resistance that is outside the valid range. Causes:

• Thermistor failed: out of resistance spec or open
• Wire harness to thermistor damaged or disconnected
• Control board input failed (less common)

F1 diagnostic

1. Disconnect power for 5 minutes: clears transient faults
2. If F1 returns immediately, pull the lower kick plate and locate the thermistor at the bottom of the tub
3. Pull the thermistor connector, check for corrosion or burned pins
4. Measure resistance: at room temperature should read 10-50 kohms depending on model. Open or zero = thermistor failed
5. Thermistor part WD21X10257 (common) about $40, 20-min replacement

F2: heating element fault

The control commanded heat but did not see the expected temperature rise. Causes:

• Heating element failed (open circuit or burned out)
• Element relay on the control board failed
• Thermistor reading incorrectly (so heat works but doesn’t register)

F2 diagnostic

1. Visual check the heating element through the tub: discoloration, breaks, or sagging? Burned element will not heat
2. With power off, ohm the element across its terminals: healthy reads 10-25 ohms, open or shorted reads way off
3. If element reads good, the relay or the control is the issue; escalate to a tech
4. Heating element part WD27X10025 about $55, 45-min replacement (drain tub first)

F3, turbidity sensor

GE Profile dishwashers have an optical turbidity sensor that detects how dirty the wash water is. The control adjusts wash time based on this reading. When the sensor reads improbable values, F3 triggers.

F3 diagnostic

1. The sensor is in the sump area, behind the filter
2. Remove the filter, look for the small clear lens at the sump bottom
3. Clean the lens: food particles, grease, or scale on the lens fool the optical reading
4. If cleaning does not clear F3, the sensor itself failed: part WD21X10374 about $75, 30-min replacement

The water hardness factor

In Miami, F3 codes appear more often because hard-water scale builds on the turbidity sensor lens. If F3 has been intermittent for months and clears after a vinegar cycle, scale is the root cause. Monthly descaling (see our Miami hard-water guide) prevents F3 entirely.

The combined fault pattern

If you see F1 + F2 together, both the thermistor and the element are involved. Usually means the element burned out, took the thermistor’s resistance reading with it (thermal stress), and both failed within hours. Plan to replace both.

Cycle-power reset

Before ordering parts, always try a 5-minute power-off reset. About 20% of F-codes are RAM corruption from South Florida brownouts and clear with a hard reset.

Cost summary

• F1 thermistor: $40 part, 20-min DIY or $180 service
• F2 heating element: $55 part, 45-min DIY or $230 service
• F3 turbidity sensor: $75 part, 30-min DIY or $210 service
• F3 from scale: $0, vinegar cycle and ongoing maintenance

Related: GE repair | Dishwasher repair | Service in Hollywood