B1422
Book Code B1422 Inspection
Automotive Climate Control
Critical Risk - Turn Off AC
Code B1422 - Compressor Lock Sensor Circuit (Toyota / Lexus)
A critical code indicating that the A/C ECU detected a speed difference between the engine crank pulley and compressor shaft, meaning the compressor is slipping or locked to protect the serpentine belt.
Safe to Drive? ❌ No, Turn Off AC
Estimated Repair Cost 350 - 2200 SAR
Common Makes Toyota, Lexus
System Category compressor
Symptoms of Trouble Code B1422:
- ⚠️ Sudden loss of cooling, blowing hot air
- ⚠️ A/C button light flashes / blinks continuously
- ⚠️ Squealing belt noise or burning rubber smell from engine bay
- ⚠️ A/C compressor magnetic clutch automatically disengaged by ECU
Common Causes Behind Code B1422:
- 🔍 Internal compressor mechanical seizure due to oil starvation or wear
- 🔍 Defective compressor revolution/lock sensor mounted on compressor body
- 🔍 Loose, cracked, or worn serpentine drive belt
- 🔍 Failing magnetic clutch assembly
Diagnostic Procedure Recommended by Auto Save Technicians:
- 1 Stop car and immediately turn off AC switch
- 2 Visually inspect serpentine belt for cracking, fraying, or rubber glazing
- 3 With engine OFF, check if compressor hub spins freely by hand or is seized tight
- 4 Measure lock sensor resistance (typically 65 to 125 ohms)
Specialist Recommendation:
Request Parts & Repair Quote
Turn off A/C immediately and visit a workshop before belt snap.
Associated Components: A/C Compressor Lock Sensor Serpentine Belt Magnetic Clutch
Frequently Asked Questions: Code B1422
Why is my Toyota A/C light blinking?
A blinking A/C light in Toyota is a warning that code B1422 was triggered and the ECU cut compressor power to prevent belt failure.