Outdoor unit starts and stops repeatedly, E6 code logged, compressor may not start reliably

Safety first: Turn off power at the disconnect and verify with a meter. Capacitors can hold a charge—discharge them properly before handling.

Steps:

• 1. Listen for symptoms: When calling for cooling, listen at the outdoor unit. A loud hum followed by a click without the compressor starting suggests a start issue.
• 2. Inspect contactor: Remove the control panel cover. Check the contactor for pitted or burned contacts. With power off, ensure all lugs are tight.
• 3. Test capacitor: Locate the dual run capacitor (often serving both fan and compressor). Discharge it, then test capacitance with a meter. Compare to the µF rating on the label. Replace if more than 10% out of spec.
• 4. Check compressor wiring: Verify all compressor terminals are firmly connected and not burned. Replace any overheated spade connectors.
• 5. Attempt restart: Restore power and call for cooling. If the compressor still fails to start and E6 returns, the compressor may be mechanically locked or internally damaged.
• 6. Do not repeatedly reset: Repeated attempts can overheat and damage the compressor. Contact a professional for further testing (megohm test, amp draw, etc.).