B1250 on Ford
Air Temperature Internal Sensor Circuit Failure
B1250 on Ford vehicles indicates air temperature internal sensor circuit failure. Au7o has documented this code across 1 Ford model — most commonly on Explorer. Ford manufacturer-specific body code (also seen on Lincoln/Mercury and Ford-derived Mazda models). The in-cabin (interior) air temperature sensor that feeds the automatic climate control module has returned an out-of-range or missing signal. The climate control system loses the reference it uses to decide how much heat or A/C to deliver, so automatic temperature control stops regulating properly and may blow full hot or full cold. Ford's own pinpoint tests cover the sibling codes B1251 and B1253 as open- and short-to-ground faults on the same circuit, so the wiring is as suspect as the sensor itself. Typical repair costs on Ford range from $25 to $350, depending on the specific model and root cause.
Common Causes of B1250
- •Failed interior (in-car) air temperature sensor
- •Open, shorted, or chafed wiring in the sensor circuit
- •Corroded or backed-out sensor connector pins
- •Blocked or disconnected aspirator hose/tube feeding cabin air to the sensor (on models that use one)
- •Faulty climate control module (EATC/HVAC head unit)
B1250 on Ford by Model
Ford Explorer(1 issue)
- HVAC Blend Door Actuator Failure Causing Clicking Noise and No Heat or A/C2011-2019
The temperature/blend door actuator is a very common failure on the Explorer (shared with Taurus, Flex and Lincoln MKS/MKT). The actuator's internal plastic gears strip, producing a repeated clicking or knocking sound behind the dash and leaving the cabin stuck on hot or cold, or blowing the wrong temperature on one side. On older (2002-2010) Explorers the same symptom appears on the floor/mode and blend actuators. It is an inexpensive part but the noise and inability to control cabin temperature are constant annoyances.
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What does B1250 mean on Ford?▼
B1250 stands for "Air Temperature Internal Sensor Circuit Failure." Ford manufacturer-specific body code (also seen on Lincoln/Mercury and Ford-derived Mazda models). The in-cabin (interior) air temperature sensor that feeds the automatic climate control module has returned an out-of-range or missing signal. The climate control system loses the reference it uses to decide how much heat or A/C to deliver, so automatic temperature control stops regulating properly and may blow full hot or full cold. Ford's own pinpoint tests cover the sibling codes B1251 and B1253 as open- and short-to-ground faults on the same circuit, so the wiring is as suspect as the sensor itself. On Ford specifically, this code is documented across 1 model.
What causes B1250 on Ford vehicles?▼
Common causes on Ford: Failed interior (in-car) air temperature sensor, Open, shorted, or chafed wiring in the sensor circuit, Corroded or backed-out sensor connector pins, Blocked or disconnected aspirator hose/tube feeding cabin air to the sensor (on models that use one), Faulty climate control module (EATC/HVAC head unit). Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix B1250 on a Ford?▼
Repair costs on Ford range from $25 to $350, depending on the specific model and root cause.
Which Ford models have B1250 documented?▼
Au7o has documented B1250 on 1 Ford model: Explorer.