DIAGNOSIS: Intermittent headlight operation points to a poor electrical connection, not a burnt-out LED. The primary suspect is the connector inside the stem.
FIX: 1. Fold down the handlebar stem. 2. Locate the rubber boot covering the wiring where the stem meets the deck. 3. Carefully open the boot and find the multi-pin connector. Disconnect it, inspect for bent pins or corrosion, and firmly reconnect it. 4. Check the connection at the back of the headlight housing itself, accessible by removing the plastic cover.
IF THAT DIDN'T WORK: The issue may be the wire harness itself, which can suffer internal breaks from repeated folding. This requires replacing the main stem wiring loom.
HEADS UP: Do not tug on the wires directly. Always grip the plastic connector housings when disconnecting. Ensure the stem is folded down before checking connections to avoid stretching the wires.