Why is my Lexus IS 200t A/C, heat, or airflow not working? This Lexus IS guide is based on 3 documented technical cases, including 3 confirmed successful repair outcomes. It summarizes the captured evidence without assuming every vehicle with a similar symptom has the same cause. Documented applicability includes 2015–2016.
What Drivers or Technicians Reported
Documented complaints included: A/C compressor will not engage and A/C-button lamp blinks.; Passenger vents blow hot while driver side follows command.; MIL illuminated with bank-2 sensor-2 heater code..
Fault Codes Seen in Supporting Cases
Codes included B1422, B1441-41, B1453-53, B1454-54, P0057. A code is a diagnostic clue, not automatic proof that a specific part failed.
Causes Confirmed in Documented Cases
Failed Power Integration ECU/internal non-serviceable relay. Failed right blend-door actuator motor. Slow/failing bank-2 sensor-2 oxygen-sensor heater.
What the Diagnostic Process Found
Power for about three seconds, then cut off Compressor operated and cooled normally Moved freely Bank 2 slow to respond
Repairs That Corrected Documented Cases
Replace Integration ECU Replace right blend-door actuator and calibrate Replace OEM bank-2 sensor-2 O2 sensor; clear adaptives
Repairs or Attempts That Did Not Solve the Original Problem
Replace complete A/C compressor — unsuccessful
Lexus IS Diagnosis in Hickory, NC
Mich's Foreign Cars has served Hickory and the surrounding Western North Carolina area since 1983. We specialize in European and foreign vehicles and use professional diagnostic equipment to identify the cause before recommending repairs. If your Lexus IS is showing this symptom or fault pattern, call Mich's Foreign Cars at 828-324-6012 to schedule diagnosis.