<<<My LG Tromm will spin (when I push start), but won't start the cycle (just keeps spinning)...intermittently.>>>
Washer *tumbles* (rotates) erratically/intermittently?
<<<I also intermittently get the door code (DE) at start with associated chime>>>
<<<I don't know if these two issues are related or if I have two separate pending failures.>>>
All LG WM2277 washers have the older HALL EFFECT SENSOR (6501KW2002A
The resistor inside the original HALL EFFECT SENSOR (also called Rotor Position Sensor) is sensitive to overuse of detergent (high load during RINSE cycle).
Nearly all detergent manufacturers instruct consumers to use too much HE (High Efficiency/Low Suds) type deteregent.
The ***correct*** amount is as follows:
HE: (2) Tablespoons Per Wash
HE 2X (double concentrated): (1) Tablespoon
HE 3X (triple concentrated): (1) Teaspoon
Failure to use the correct amount in older LG washers---will eventually damage the Hall Effect Sensor.
Beginning in early 2008---newer Hall Effect Sensors replaced the original---having a much more robust *resistor*.
I've *never* had a failure---of the new Sensor.
The Hall Effect Sensor provides data feedback to the Main Board
1) Direction of tub rotation
2) Speed of Motor/Tub
3) Weight of Laundry
4) Electrical Load of Motor (primarily for suds detection during RINSE)
5) Prevents the door from *unlocking* until the tub comes to a complete stop (safety).
Judging by your description (and my own personal experience)---it would appear that the Hall Effect Sensor has NOT *completely* failed.
Some data feedback is insufficient or missing entirely (from the Hall Effect Sensor-to-the-Main Board)
When a cycle is started---the first action that occurs---is measuring the *dry* weight of the laundry in the tub.
Then a partial fill of water occurs---to get the clothing/fabrics somewhat wet.
Based on these variables (weight feedback from the Sensor) the Main Board will "know" how much water is needed to wash the weight of the laundry in the tub.
If the data feedback is missing or incomplete---the washer will behave differently than it nomally does (waiting/attempting to receive feedback/stalled).
In most cases a failed Hall Effect Sensor will trigger an "LE" error---but not always.
It's also less expensive than a Main Board---replace the Hall Effect Sensor first
The part number has NOT been changed---and remains the same (6501KW2002A