OBD-II trouble code
P0074: Ambient Air Temperature Sensor Circuit Intermittent
Application matters: Locate the actual outside-temperature sensor and reporting/receiving modules using the vehicle’s diagram. The display, raw scan parameter and engine-controller input may use different paths or update rules; the generic code does not identify connector pins.
P0074 identifies an intermittent circuit fault involving ambient/outside-air temperature information. Check the complete code and actual sensor/module path before replacing a sensor or climate-control part.
Quick facts
- System
- Powertrain
- Category
- Temperature
- Severity
- Low severity
- Driving guidance
- Depends on symptoms and vehicle guidance
- Repair cost range
- $152 – $211 (ambient air temperature sensor replacement, parts and labor; conditional job example)
- DIY difficulty
- Intermediate DIY
A code alone cannot establish whether driving is safe. Stop safely for a red brake or oil-pressure warning, overheating, severe misfire, stalling, or impaired braking or steering, and follow the owner's manual. Restraints faults can reduce crash protection even when the vehicle runs normally.
Part of a family with 5 codes
P0074 is one of 5 codes covering ambient air temperature input faults. The identifier must be matched to the exact vehicle. Related codes can share a diagnostic approach, but their circuit, failure condition, and required tests can differ.
Read the full guide for this family →Browse every code in P0001–P00C6, or start from the full code library.
What does P0074 mean?
P0074 identifies an intermittent circuit fault involving ambient/outside-air temperature information. An intermittent result describes a fault detected during monitoring. It does not mean all static measurements are useless, that the circuit is currently perfect or that the problem must become a permanent fault.
Ford’s TSB 16-0054 describes certain 2014–2016 Transit Connect 2.5L vehicles with intermittent outside-temperature/display or A/C complaints and P0073/P0074/U0422. For the listed 2017–2019 Buick LaCrosse and 2016–2019 Chevrolet Malibu VIN Z vehicles with the specified VRI/WMI options, GM 16-NA-051 separates sealed-connector corrosion from snow/ice-related active-shutter obstruction. Match the condition and complete fault list before selecting the repair.
Save the complete scan results, identify the physical sensor and trace how the relevant controller obtains its value. A displayed default, a single outlier or one good reading does not identify the failed component. Do not bridge unknown terminals, use a generic resistance/voltage curve or treat an unplug response as proof that every wire and module is good.
Outside-temperature information can affect the display and climate functions on vehicles that use it. A temperature-related A/C complaint does not establish a refrigerant problem. Follow the actual vehicle’s operating and visibility warnings; the code alone does not guarantee unchanged engine or climate operation.
Possible causes
- A loose, contaminated, damaged or intermittent connection in the identified sensor path
- A sensor/input accuracy or internal fault demonstrated by its permitted checks
- An open, short or excessive resistance established by the actual circuit tests
- Disturbed mounting, routing or a recent repair affecting the actual sensor installation
- A receiving-module, communication or configuration fault established for the actual input path
Symptoms
- Check engine light or stored P0074
- An inaccurate, absent or changing outside-temperature display, where equipped
- Changed automatic climate or A/C operation, depending on vehicle strategy
- Related electrical, module or communication codes
- An intermittent fault with a plausible current display; this does not verify the complete path
Diagnostic steps
Save the full scan report, code status, and available freeze-frame data before clearing anything. Confirm the reporting module, any failure-type suffix, and the procedure for the exact vehicle. The steps below are an overview; use manufacturer specifications and safety procedures for testing.
- 1.Save the full P0074, reporting module, suffix, status, event information and companion codes. Note the displayed temperature, actual conditions and recent body, mirror or sensor work.
- 2.Identify the actual sensor location and which module measures, passes through or receives the input. Use the vehicle’s diagram rather than an assumed bumper, mirror or direct-ECM arrangement.
- 3.With the vehicle safely parked and the affected area accessible, inspect for visible connector, seal, mounting or harness damage. Keep clear of fans, hot components and active shutters; do not force a shutter or work under an unsupported vehicle.
- 4.Record when the fault occurs and have a technician review stored/event and live data under permitted conditions. Do not deliberately hit bumps, spray connectors or manipulate wiring near moving/hot parts to provoke it.
- 5.Use only specified terminals, isolation methods and test equipment. A jumper, unplug response or one resistance measurement is not a universal sensor-versus-harness verdict.
- 6.If the vehicle matches Ford 16-0054, have the shop check the exact bulletin conditions and current procedure before its conditional sensor/connector repair. A generic code alone does not establish applicability.
- 7.If the vehicle matches GM 16-NA-051, distinguish the specified connector-corrosion and active-shutter/weather branches. Do not replace an unrelated sensor or shutter solely from the code.
- 8.Repair the demonstrated cause, then verify the relevant input path, display/climate complaint and required monitor under safe conditions. A brief good display or code clearing alone is not proof.
Repair cost
$152 – $211 (ambient air temperature sensor replacement, parts and labor; conditional job example)
USD planning figures, not a vehicle-specific quote. Confirm the diagnosed job and whether the estimate includes diagnosis, parts, labor, programming, calibration, and taxes.
RepairPal national estimate, updated September 3, 2026 and checked November 6. Applies only if sensor replacement is diagnosed. Excludes taxes, fees, location differences and related repairs. Diagnosis, a connector/harness repair, module work and other climate-control repairs require separate quotes.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with check engine light diagnosis preselected. Adjust labor rate and vehicle category to fit your situation.
Related repairs
These links are planning examples; the code does not confirm that any listed part has failed.
DIY vs shop
Diagnosis or repair may suit an experienced DIY owner with the correct service information and tools. Check access, lifting requirements, electrical precautions, and any setup procedure before starting. A code alone cannot establish the repair time or difficulty.