Brand:LG
Model Number: LFXS29766S/01
Main Symptom: new ice maker will only drop ice if reset
What happens & when: draws water but doesn’t release ice.
Error Code (if any):none
Parts or tests already tried: second ice maker tried. Cleaned coil. Freezer temp -5.
Photos / video link:
With two ice makers doing the exact same thing, I would stop replacing the ice maker. The important clue is that pressing RESET/TEST makes it harvest, but it will not initiate that harvest automatically.
On the LFXS29766 series, the control waits for the ice maker’s temperature/logic conditions and then uses the Hall sensor/ejection circuit to initiate and confirm harvest. The service manual specifically says temperature, time, the ice-full signal, Hall sensor, wiring, and control are involved in automatic ejection.
1. Verify the actual temperature at the ice maker — not the freezer setting.
Your freezer being set to -5°F is plenty cold, but this model’s primary ice maker is in the refrigerator-door ice compartment, so freezer temperature alone doesn’t prove the ice maker itself is cold enough.
Put a thermometer or thermocouple right beside the ice maker/tray and leave the doors closed for a couple hours. The service information indicates the ice-making compartment needs to get to approximately 1°F or colder for the normal dump sequence.
If that compartment is substantially warmer, concentrate on the ice-room airflow system, especially the icing/ice fan (Er IF circuit), ducting, and ice-room door/seals.
2. Check the ice/icing fan.
This is high on my list. The LFXS29766 service manual gives the icing-fan diagnostic and specifies approximately 11.4–12.6 VDC from the main PCB in Test Mode 1 for the icing fan circuit.
A fan can also run but move very little air because of frost/ice around the fan or duct.
So check:
Cleaning the condenser coil won’t correct an ice-room airflow problem.
3. Check the ice-bin/full-ice sensing system.
The automatic sequence checks whether the bin is full before initiating harvest. If the control falsely sees “ice full,” it can leave frozen cubes sitting in the mold even though the ice maker itself works. The service manual describes the ice-full/Hall-sensor logic as part of the automatic harvest sequence.
Remove the bin and make sure the sensing mechanism/path isn’t obstructed.
If you press RESET and:
Tray twists → ice drops → tray returns → water refills, that’s actually very useful.
It proves quite a bit:
Since you’ve duplicated that behavior with two ice makers, the odds of two defective ice makers causing exactly the same failure are fairly low.
I would go:
Ice-room temperature → ice/icing fan and airflow → ice-full sensing → wiring/connectors → main control board.
If the temperature at the ice maker is around 0°F and the ice-full system isn’t falsely indicating a full bin, then I would start checking the harness between the ice maker/door and main PCB. If those circuits check good, the main PCB becomes the leading suspect, because the automatic harvest command isn’t occurring even though a forced harvest works.
Also, LG specifies 0°F as the normal freezer setting for ice production, so your -5°F setting is already more than adequate; I wouldn’t lower it any further.
If you give me the part number of the ice maker you installed, I can narrow this down further and give you the connector/pin voltage checks for the ice maker, ice fan, and main board.
The thermometer inside the ice maker is reading -5 and the ice maker part is AEQ73130004. Is there a way to know if the fan is working without taking it apart? I may need to call a repair guy for that. Than you
If you can access the fan, a neat trick I did to see if it was running if I couldn’t hear it was to stick a piece of tape to one blade then run it. Usually if the tape is hitting the housing you can hear it or if you recheck it after letting it run the marked blade location will have changed.
Yes — AEQ73130004 is the correct LG Slim SpacePlus ice maker assembly for the LFXS29766S series. Multiple parts references specifically list LFXS29766S as compatible.
That strengthens the diagnosis because you’ve now tried two correct ice makers, and both will harvest when TEST/RESET is pressed.
The service manual shows that automatic harvesting depends on the ice maker’s Hall IC signals and temperature/ice-making logic. During a forced test, you’re essentially commanding the ice maker to bypass the normal wait conditions and perform the harvest sequence.
First test the actual temperature inside the upper ice compartment. Don’t use the freezer temperature for this test. Put a thermocouple right beside the AEQ73130004 mold and let the refrigerator operate normally with the door closed.
If that compartment isn’t getting sufficiently cold, the ice maker can fill and freeze the water but never satisfy the automatic harvest conditions.
This would be my #1 suspect before the main board.
The upper ice maker is in the refrigerator door and depends on cold air supplied to the ice compartment. Check:
If you have approximately 12 VDC supplied but the fan isn’t turning normally, replace the fan.
The service manual gives us another useful clue. The AEQ73130004 determines mold position using its Hall IC. The board looks for HIGH/LOW Hall signals to determine mold position and control ejection.
Normally I’d suspect that circuit when the ice maker won’t harvest. But you’ve installed two ice makers and both behave identically. That makes two bad Hall sensors considerably less likely.
So I’d inspect the ice-maker harness and connectors, particularly where the wiring passes through the door/hinge area. Look for:
Let it make ice normally and do not press RESET.
Once you know the cubes are completely frozen and it has failed to dump them, measure the temperature right at the ice maker.
If you find something like:
Ice compartment too warm → chase the ice fan/airflow problem.
Ice compartment properly cold + frozen cubes + bin isn’t full + won’t harvest → harness/Hall-signal circuit or main PCB.
Since RESET consistently makes AEQ73130004 dump, return home, refill, and then freeze another batch, I’d put the parts in this order:
1. Ice-room temperature/ice fan
2. Ice-maker harness/connectors
3. Ice-full sensing circuit
4. Main control PCB
I would not buy a third AEQ73130004. At this point the evidence is pointing outside the ice-maker assembly.
Live voltage warning: several of these checks are made with the refrigerator powered. Keep meter probes from shorting adjacent pins.
| Check | Where to test | Expected reading | What it tells you |
|---|---|---|---|
| Ice/icing fan supply | Main PCB CON7 icing-fan output to DC ground in Test Mode 1 | 11.4–12.6 VDC | Proper board supply to ice fan |
| Ice fan feedback | Fan feedback line to DC ground, fan running | Should switch/pulse between roughly 0 and 5 VDC, not stay permanently 0 V or 5 V | Confirms fan rotation feedback |
| Freezer fan supply | Main PCB CON7 freezer-fan output to DC ground, Test Mode 1 | 11.4–12.6 VDC | Useful comparison/check of board DC fan supply |
| Ice-room sensor | Main PCB CON5, ice/icing sensor circuit | Resistance varies with temperature | Confirms board can determine ice-room temperature |
| Ice-maker supply | Backprobe ice-maker connector power and ground | Supply should remain present during normal operation | Rules out intermittent door/harness power loss |
| Hall/position signals | Ice-maker Hall signal wires referenced to signal ground | Typically change between approximately 0 and 5 VDC as mold moves | Confirms mold-position information reaches control |
| Water valve output | Ice valve during fill portion of forced harvest | Approximately 120 VAC while energized | Already essentially proven since yours fills |
| Main board input | L1 to Neutral | Approximately 120 VAC | Confirms proper PCB line supply |
LG specifically gives 11.4–12.6 VDC as the expected icing-fan output in Test Mode 1. The service literature also uses a 0/5-V feedback signal for the electronically controlled fan circuits.
Put the refrigerator into Test Mode 1 using the test button on the main PCB.
Then check the icing fan circuit at CON7.
You want:
11.4–12.6 VDC
If you have 12 VDC at the PCB but not at the fan, trace the harness/connectors.
If you have 12 VDC at the fan and it doesn’t run, replace the fan.
If you do not have 11.4–12.6 VDC coming from the PCB during Test Mode 1, the main PCB becomes suspect. LG’s troubleshooting chart specifically uses this test for the Er IF/icing-fan circuit.
Don’t stop just because the fan spins.
The fan has a feedback circuit that tells the control it is actually rotating. Check the feedback wire relative to the fan’s DC ground while it’s operating.
It should be a changing/pulsing 0–5 VDC signal. A normal meter may show an unstable/intermediate number because it is averaging the pulses.
If:
12 V supply good + ground good + fan spinning + no feedback signal → fan or feedback wire problem.
This could potentially prevent proper ice-room cooling without immediately looking like a dead fan.
This is especially important for your symptom.
LG identifies the icing sensor circuit at main PCB CON5. The control has to know that the ice compartment is cold enough before normal automatic ice ejection occurs.
Unplug the refrigerator before resistance testing.
Measure the icing thermistor through its harness at the main board. The exact resistance changes with temperature; what’s important initially is that it isn’t:
OL/open
0 Ω/shorted
wildly inconsistent with actual temperature
Also measure the actual temperature beside the ice maker. LG states the ice-maker compartment needs to reach approximately 1°F or colder before the normal dump sequence occurs.
This is the one I’d pay particular attention to given that two ice makers act identically.
With the connector plugged in, backprobe rather than disconnecting it.
You are looking for three things:
Power — present continuously as designed.
Ground — good, essentially 0 V drop.
Hall/position signals — changing HIGH/LOW as the tray moves.
The AEQ73130004 uses Hall IC feedback to determine the mold position. LG describes the control watching HIGH and LOW Hall signals as the ejector moves. If those signals don’t change correctly, automatic operation can stop.
During a forced harvest, watch the Hall signal with your meter.
You should see it transition between approximately:
LOW ≈ 0 VDC
HIGH ≈ 5 VDC
The service manual explains that if the expected Hall change doesn’t occur during ejector operation, the control treats the motor/Hall circuit as abnormal.
Because the ice maker is in the door, I would check the harness at the upper left-door hinge connector while doing these measurements.
This is a good test:
Start a forced harvest and gently move the door/harness while watching the Hall/supply voltage.
Any voltage dropout or sudden signal change strongly points toward:
broken conductor inside the door harness
loose terminal
backed-out connector pin
corrosion/moisture in connector
That would also explain why two different ice makers behave identically.
Since TEST makes yours harvest and refill, this circuit is basically already proven, but if you want to document it:
Meter on AC volts across the ice-maker water valve coil during the fill portion of the forced harvest.
You should briefly see approximately:
120 VAC
Then it should disappear when filling ends.
Do not expect continuous voltage there.
I’d run it in this order:
1. Actual ice-room temperature right beside AEQ73130004
Must be about 1°F or colder when you’re expecting an automatic harvest.
2. Icing fan
Test Mode 1:
11.4–12.6 VDC supply
Then verify fan operation and feedback.
3. Icing thermistor
Check resistance through the harness at the main board and compare it with actual ice-room temperature.
4. AEQ73130004 supply/ground
Make sure neither disappears between harvests.
5. Hall-position signal
Watch for approximately 0 ↔ 5 VDC transitions during forced harvest.
6. Door/hinge harness
Continuity plus wiggle test.
7. Main PCB
If the ice compartment is properly cold, fan supply/feedback is correct, thermistor is reporting correctly, ice maker has proper power/ground, and Hall information gets all the way back through the harness, then I would replace the main PCB.
The key fact here remains that pressing TEST causes the mold to eject, return home, and refill. LG’s manual confirms that the normal cycle depends on temperature, bin-full status, motor movement, and Hall-position feedback, while the TEST function forces the operation.
So with two AEQ73130004 assemblies giving the same symptom, I would concentrate heavily on the icing thermistor/ice-room temperature and Hall-signal wiring before the board.