Bryant system displays code 53; indicates outdoor temperature sensor fault. System may not operate correctly in low or high ambient conditions.

Safety first: Turn off power to the outdoor unit.

Steps:

• 1. Locate sensor: Find the outdoor ambient temperature sensor (thermistor) typically mounted on the Bryant condenser cabinet away from direct sunlight and discharge air.
• 2. Inspect mounting: Ensure the sensor is firmly attached and not dangling near the hot discharge air stream. Reposition if necessary according to the installation manual.
• 3. Check wiring and connector: With power off, inspect the sensor leads and connector for damage, corrosion, or rodent chewing. Clean and reseat the connector.
• 4. Reset and test: Restore power and check if the thermostat now displays a reasonable outdoor temperature and if code 53 clears.
• 5. Replace sensor if needed: If the reading is obviously wrong (e.g., 150°F on a mild day) or code persists, the thermistor is likely bad and should be replaced with the correct Bryant part.

Note: Sensor resistance can be checked with a multimeter and compared to Bryant's temperature/resistance chart by a technician.