If your LG dishwasher is not filling with water after replacing parts, it can be incredibly frustrating. You’ve already changed the inlet valve, drain pump, and even the soap dispenser, but the machine still runs without water.
You may hear the drain pump and circulation pump working, yet no water enters the unit. At this point, guessing can get expensive, so proper diagnosis is key.
Quick Answer
If your LG dishwasher won’t fill with water, even after replacing the inlet valve, the issue is likely a faulty water flow sensor, float switch, or control board signal problem.
Step-by-step solution to fix LG dishwasher not filling with water
Step 1: Confirm water supply again (don’t skip this)
Even if it seems obvious:
- Ensure water valve is fully open
- Disconnect line and verify strong flow into a bucket
You already confirmed this, so move to internal checks.
Step 2: Observe the initial cycle behavior
You mentioned:
- Drain pump runs → normal startup
- Circulation pump runs → system thinks water is present
- No water enters
This suggests a sensor or control issue, not supply.
Step 3: Check the water flow sensor (fill sensor)
This is a critical component.
- It detects incoming water
- If faulty, the dishwasher assumes no water flow
Test it by:
- Checking voltage at control board connector (NA8 pins 1–2)
- Using a multimeter
If no signal or incorrect readings → replace the sensor.
Step 4: Inspect the float switch assembly
The float prevents overfilling.
- If stuck or faulty, it may block water entry
Check for:
- Debris under the float
- Stuck position
- Electrical continuity
A stuck float can stop filling completely.
Step 5: Recheck inlet valve wiring
Even with a new valve:
- Confirm voltage reaches the valve during fill cycle
- Check connectors are:
- Secure
- Not reversed or loose
No voltage = control issue.
Step 6: Inspect control board (PCB)
Since multiple components were replaced:
- The control board may not be sending power to the valve
Check for:
- Burn marks
- Loose connectors
- Corrosion
The board controls:
- Water inlet
- Pump timing
- Sensor input
Step 7: Consider soap dispenser installation impact
You replaced the soap dish:
- Ensure no wires were disturbed
- Check door wiring harness
A loose connection here can affect signals to the control board.
Step 8: Try diagnostic/test mode (if accessible)
Even though you had trouble:
- Double-check correct button sequence for your exact model
- Some models require:
- Door closed
- Specific timing between button presses
If test mode fails:
- It may confirm a control board issue
Step 9: Add water manually for testing
You already did this, which is great.
- Dishwasher runs normally with manual water → pumps are OK
- Confirms problem is strictly water intake system
Extra tips and best practices
- Always test voltage before replacing parts
- Take photos before disconnecting wiring
- Use service manual flowcharts for guided diagnosis
- Replace sensors before expensive boards when possible
- Keep connectors clean and dry
Common mistakes to avoid
- Replacing parts without testing signals
- Ignoring sensors (flow sensor is often overlooked)
- Assuming new parts are always good
- Skipping wiring checks after installation
- Overlooking control board faults
FAQ
Why does my dishwasher run but not fill with water?
Because it may incorrectly detect water presence due to a faulty sensor.
Can a bad flow sensor stop water filling?
Yes. The system relies on it to confirm water entry.
Why are there no error codes?
Some failures (like sensor faults) don’t always trigger error codes.
Conclusion
If your LG dishwasher is not filling with water after replacing the inlet valve, the issue is likely deeper. Based on your symptoms, the most probable causes are a faulty water flow sensor, float switch issue, or control board failure.
Focus on testing signals before replacing more parts. That’s the fastest way to fix it without unnecessary costs.
Reference Links
https://www.lg.com/support
https://www.ifixit.com/Device/Dishwasher
https://owner.electrolux.com/support-articles/article/1819543-dishwasher-not-drying
