Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2007 Lexus IS 350FACTORY OEM SERVICE PROCEDURE
HVAC DTCS
HVAC DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC | Description |
|---|---|
| B1411/11 | Room Temperature Sensor Circuit |
| B1412/12 | Ambient Temperature Sensor Circuit |
| B1413/13 | Evaporator Temperature Sensor Circuit |
| B1418/18 | Exhaust Gas Sensor Circuit |
| B1421/21 | Solar Sensor Circuit (Passenger Side) |
| B1422/22 | Compressor Lock Sensor Circuit |
| B1423/23 | Pressure Switch Circuit |
| B1424/24 | Solar Sensor Circuit (Driver Side) |
| B1451/51 | Compressor Solenoid Circuit |
| B1461/61 | Emission Gas NOx Sensor Circuit |
| B1497/97 | BUS IC Communication Malfunction |
| B1499/99 | Multiplex Communication Circuit |
| B1441/41 | Air Mix Damper Control Servo Motor Circuit (Passenger Side) |
| B1442/42 | Air Inlet Damper Control Servo Motor Circuit |
| B1443/43 | Air Outlet Damper Control Servo Motor Circuit |
| B1445/45 | Front Passenger Seat Side Cool Air Bypass Damper Control Servo Motor Circuit |
| B1446/46 | Air Mix Damper Control Servo Motor Circuit (Driver Side) |
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.