Passenger Compartment Temperature Sensor Circuit Range/Performance Problem
The cabin temperature sensor is reporting a fault or abnormal reading.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The sensor that checks the temperature inside the cabin is either malfunctioning or giving readings that don't match reality, affecting climate control.
What the computer is actually seeing
The climate control module anticipates an interior temperature based on input from the sensor. When readings exceed expected ranges or fluctuate excessively (e.g., if the voltage is between 0.5V and 4.5V instead of the normal 1V to 5V), it triggers the code.
What a healthy reading looks like
Expected voltage from the sensor should be between 1V and 5V for normal cabin temperatures (20°C to 25°C).
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Inspect the wiring and connectors at the passenger compartment temperature sensor for damage or corrosion. Decision: Are they OK? If yes, move to step 2. If no, repair or replace the damaged components.
- 2Check the voltage at the passenger compartment temperature sensor connector with the ignition on. Expected voltage should be between 1V and 5V. Decision: Is the voltage within this range? If yes, move to step 3. If no, replace the sensor.
- 3Verify the operation of the climate control system. Check for proper temperature adjustments in response to changes in settings. Decision: Is the system functioning correctly? If yes, suspect the climate control module; if no, troubleshoot further.
Common causes
- Faulty passenger compartment temperature sensor
- Wiring issue between the sensor and control module
- Corrosion in connectors
- Faulty climate control module
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but you may experience inconsistent temperature control in the cabin.
Will this code come back after clearing?
If the underlying issue isn't resolved, it will likely return.
Why does this code sometimes show up with B1421?
B1421 and similar codes indicate related faults within the temperature sensing system.
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