B1412
Book Code B1412 Inspection
Automotive Climate Control
Low / Normal Under Shade
Code B1412 - Ambient Temperature Sensor Circuit (Toyota / Lexus)
Indicates an open, short, or out-of-range signal in the ambient air temperature sensor circuit behind the front grille.
Safe to Drive? ✅ Yes, Safe
Estimated Repair Cost 100 - 300 SAR
Common Makes Toyota, Lexus
System Category sensor
Symptoms of Trouble Code B1412:
- ⚠️ Dashboard cluster displays erratic outside temp (e.g. -40°C or blank ---)
- ⚠️ Poor cooling efficiency in AUTO climate mode
- ⚠️ Erratic blend door or fan behavior
Common Causes Behind Code B1412:
- 🔍 Front bumper collision damage or unplugged sensor after bumper paint/repair
- 🔍 Water ingress or environmental degradation
- 🔍 Broken wire in front radiator support harness
Diagnostic Procedure Recommended by Auto Save Technicians:
- 1 Inspect sensor behind front grille to ensure plug is securely snapped
- 2 Measure thermistor resistance (approx 1.6 to 2.5 kΩ at 25°C)
- 3 Clear DTC and verify dashboard displays realistic outdoor reading
Specialist Recommendation:
Request Parts & Repair Quote
Inspect the connector behind the front bumper grille; it is frequently just loose.
Associated Components: Ambient Air Temp Sensor Bumper Wiring Connector
Frequently Asked Questions: Code B1412
Where is the ambient temperature sensor on Toyota vehicles?
Mounted to the radiator core support directly behind the center of the front bumper grille.