Diagnostic article Generic OBD-II
P2182: Ford secondary coolant temperature fails cold-soak plausibility
Ford's documented P2182 monitor compares secondary coolant temperature with other sensors after an extended engine-off period.
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Documented application
Ford 2015 model-year diesel OBD system operation summary, revision December 22, 2014; the cited monitor only, without blanket model or engine applicability.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
Although P2182 has a broad coolant-temperature sensor 2 circuit title, Ford's 2015 diesel example uses it for a secondary coolant-temperature rationality check. The controller compares ECT2 with several other temperature inputs after a long soak. It is therefore distinct from the dedicated electrical high- and low-input codes P2185 and P2184.
The cold-soak comparison
The engine must have been off for at least six hours. Ford lists comparison thresholds of 20°C against ambient air, charge air, intake air and EGR-cooler outlet temperature. The check occurs once per drive cycle and has a typical duration of 0.5 second.
A block heater disables this check. That is a consequential exception: deliberately warming part of the engine changes the assumption that the sensors should agree after a soak.
Interpret disagreement carefully
Preserve the startup readings together, rather than treating the ECT2 value in isolation. The monitor requires acceptable status from the supporting sensors, and disagreement does not automatically prove that ECT2 is the only inaccurate input. Use the application-specific comparison and sensor diagnostic procedure. The code alone does not establish a coolant leak or justify replacing a thermostat.
Source and applicability
Ford 2015 model-year diesel OBD system operation summary, revision December 22, 2014; the cited monitor only, without blanket model or engine applicability. Ford source, physical PDF page 101. The documented monitor explains the fault decision; vehicle-specific service information is still needed for connector identification and a complete repair procedure.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
Engine Coolant Temperature Sensor 2 Circuit
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT