What This Error Means
F03 on most Whirlpool washing machines means a water temperature sensor fault (NTC sensor error). The control board thinks the water temperature reading is impossible, so it stops the cycle and flashes F03.
What is actually happening:
What is actually happening:
- The temperature sensor (NTC) in the heater or tub housing is open, shorted, or reading way out of range.
- The wiring from that sensor back to the main control board is loose, wet, burnt, or broken.
- Less common: the control board’s sensor circuit is damaged and can’t read the NTC correctly.
Official Fix
This is the straight-from-the-manual route, just in plain language.
- Kill power first
- Unplug the washer from the wall.
- Shut off water taps if you need to pull the machine out.
- Do the simple reset once
- Leave it unplugged for 5–10 minutes.
- Plug it back in, run a short warm or hot cycle.
- If F03 pops back up, the reset isn’t your fix. Move on.
- Get access to the NTC temperature sensor
- Pull the washer out so you can reach the back (or front bottom, depending on model).
- Most Whirlpool front-loaders: remove the rear panel (several screws around the edge).
- Look at the bottom of the tub: you’ll see the heater element poking into the drum housing. The NTC is a small plastic or metal probe with two wires, usually clipped into or right next to the heater.
- Check the connector and wiring
- Make sure the NTC plug is fully seated. No half-clicked connectors, no green corrosion, no burnt pins.
- Follow the wire from the sensor toward the control board. Look for cuts, crushed spots, heat damage, or places it rubs metal.
- If the wiring is obviously damaged, it needs repairing or replacing. Do not run it with taped-up bare copper touching metal.
- Test the NTC sensor with a multimeter
- Unplug the two wires from the sensor so you’re measuring just the sensor.
- Set your meter to resistance (kΩ). At room temperature, a typical Whirlpool washer NTC should be in the rough range of 10–20 kΩ.
- If you read OL / open, 0 Ω, or something way off (like a few hundred ohms at room temp), the sensor is bad.
- Replace the NTC if it’s out of spec
- Pop the old sensor out of the heater/tub housing. Some pull straight out; some have a little clip.
- Push the new sensor in fully so it seals properly and sits tight against the metal.
- Reconnect the plug firmly until it clicks or feels solid.
- If the sensor tests good, check the harness to the board
- With power still unplugged, ohm the wires from the NTC plug back to the control board connector (end-to-end on each wire).
- You want low resistance (near 0 Ω) and no short between the two wires or from a wire to chassis ground.
- Bad reading = damaged harness. Replace or repair properly with crimps/heat-shrink, not twist-and-tape.
- When NTC and wiring are both good
- At that point, the “official” answer is: replace the main control board.
- Boards are not cheap. Price it out before you commit.
- Reassemble and test
- Put panels back on, plug the washer in.
- Run a warm or hot program. Let it fill and start heating.
- If the F03 is gone and it completes the cycle, you’re done.
The Technician’s Trick
- Reseat the sensor plug like you mean it
- Most F03s I see are not dead sensors. They’re loose or oxidized connectors.
- Unplug the NTC connector and plug it back in 4–5 times to scrub the contacts.
- If you have proper contact cleaner, a tiny spray on the pins (power unplugged!) helps a lot.
- Hunt for moisture and leaks
- If the sensor or its plug is damp, the readings go crazy and trigger F03.
- Look above the sensor area: door seal, dispenser drawer, or hoses can drip right onto the wiring.
- Dry everything out thoroughly (towel + a bit of time, or a hair dryer on low, not roasting the plastic), and fix the leak if you see one.
- Use a resistor to prove the board vs sensor (diagnostic move)
- Only if you’re comfortable with a meter and electronics.
- Unplug the washer. Unplug the NTC from the harness.
- Clip a resistor (something in the 4.7–10 kΩ range) across the wiring harness side, where the sensor used to plug in.
- Reassemble enough to run safely, plug in, and start a warm cycle.
- If the washer now runs without F03, your original NTC or its wiring is the problem.
- If it still throws F03 with the resistor, the board’s sensor circuit is likely toast.
- Do not leave the resistor hack in as a permanent fix. It’s for diagnosis only.
- One more soft reset after the real fix
- After replacing the NTC or fixing wiring, unplug the washer for a few minutes again.
- Then run an empty hot cycle. If it heats and finishes, the code is properly cleared.
Is It Worth Fixing? (The Financial Verdict)
- ✅ Fix: Machine under ~8–10 years old, runs fine otherwise, and testing points to just the NTC or a simple wiring issue (usually a $10–$60 part and some labor).
- ⚠️ Debatable: Washer is older, has other problems (loud bearings, banging, rust, intermittent errors), or needs both an NTC and a pricey harness or board.
- ❌ Replace: Drum or bearings are shot, tub is rotten, or a new control board plus labor is going to land over ~50% of the cost of a decent new machine.
Parts You Might Need
- NTC temperature sensor (thermistor) – the actual water temperature sensor that triggers F03 when it fails.
Find NTC temperature sensor on Amazon - Washing machine heating element – if the element is shorted or damaged, it can sometimes take the sensor or board with it.
Find heating element on Amazon - NTC wiring harness / pigtail – if the sensor wiring is burnt, brittle, or corroded beyond a clean repair.
Find NTC wiring harness on Amazon - Main control board (PCB) – only if the sensor and wiring test good but F03 will not clear.
Find control board on Amazon - Heater gasket / seal – useful if the old heater or sensor seal is weeping and you have to disturb it during the repair.
Find heater gasket on Amazon