B1250 on 2011-2019 Ford Explorer — Air Temperature Internal Sensor Circuit Failure
1 vehicles · 1 makes · $25-$350 repair
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Ford Explorer · 2011–2019
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.
Common Symptoms
- Repeated clicking/knocking behind dash
- No heat or no cold air
- Different temperature left vs right
- Air won't change temperature with knob
How to Fix
Replace the failed blend door actuator. For 2011-2019 Explorer the OEM unit is Motorcraft YH-1779 (Ford AA5Z-19E616-C; aftermarket Dorman 604-234), about $25-$35; labor is short for the accessible actuator (~0.5 hr) but can be much higher if it is a deep-dash unit. Confirm the blend door itself isn't broken (door drive can shear) before/after replacement if clicking persists.
Sources for this issue (1)
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B1250 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does B1250 mean?
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.
What are the most common causes of B1250?
The most common causes of B1250 are: 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). The specific cause varies by vehicle.
How much does it cost to fix B1250?
Repair costs for B1250 range from $25 to $350, depending on the vehicle and root cause.
Which vehicles are affected by B1250?
Au7o has documented B1250 across 1 vehicle models from 1 manufacturers: Ford.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.