How to Fix Diagnostic Code P1193

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🚨 Diagnostic Profile

Vehicle Make: Dodge

Fault Description: Inlet Air Temp Circuit High. This indicates the Powertrain Control Module (PCM) is reading an intake air temperature sensor signal above the expected range, typically associated with an open circuit, high resistance, or a failed sensor. Generic OBD-II reference is commonly P0113 (Intake Air Temperature Circuit High Input), to be confirmed with a scan tool on this specific vehicle.

Technician Note: Exact year, model, and engine were not specified for this report. Before ordering parts or applying circuit-specific values, confirm the platform via VIN decode or scan tool ECU identification, as IAT sensor location and whether it is a standalone sensor versus integrated into the MAP or MAF sensor assembly varies across Dodge model years. On the majority of Dodge/Chrysler-group PCM architectures, the IAT sensor is a negative temperature coefficient (NTC) thermistor fed by a PCM-supplied reference voltage, and the diagnostic logic below applies broadly across these platforms.

🚨 Repair Difficulty Tier

Tier: Intermediate

Sensor replacement is generally straightforward, but accurate diagnosis requires a digital multimeter, scan tool data review, and wiring harness inspection. Escalate to Professional Only if the fault involves PCM replacement, requires module reprogramming, or involves harness repair within a shared/splice connector affecting other circuits.

🛠️ Resolution Steps

Step 1: Preliminary Inspection

  • Verify the DTC and freeze frame data with a scan tool and record the current IAT live data value, along with coolant temperature and engine run time at the time of fault.
  • Perform a visual inspection of the intake air temperature sensor connector for corrosion, bent pins, moisture intrusion, or loose seating.
  • Inspect the intake tract and air filter housing for cracks, loose clamps, or vacuum leaks that could affect sensor readings or expose the sensor to unmetered air.
  • Check the wiring harness for chafing, rodent damage, or heat damage near the sensor location, typically found in the air filter housing, intake manifold runner, or integrated into the MAF/MAP sensor body depending on platform.
  • Review technical service bulletins (TSBs) and recall information specific to this Dodge model and model year for known IAT circuit concerns.

Step 2: Diagnostic Verification

  • Compare the scan tool IAT reading with ambient temperature when the engine is cold (key-on, engine-off, soaked for several hours). Readings should closely match actual ambient air temperature; a circuit-high fault will typically display an unrealistically low or maximum-scale temperature reading (near -40°F/-40°C) due to the open circuit being interpreted as cold by the PCM.
  • Check for reference voltage (typically 5V) at the sensor connector signal circuit using a digital multimeter against a known good chassis ground, with the connector disconnected and key on, engine off.
  • Measure sensor resistance at the sensor itself (connector disconnected) at known ambient temperature. NTC-type IAT sensors used across most Dodge platforms typically read several thousand ohms near room temperature (roughly 2,000–3,000 ohms at 70°F/21°C) and decrease significantly as temperature rises; consult the specific service manual resistance-vs-temperature chart for this exact application to confirm pass/fail values.
  • Perform a continuity and resistance test on the signal and ground circuits between the PCM connector and sensor connector with both disconnected and ignition off; resistance should read near zero ohms (effectively a dead short/continuous circuit) with no significant voltage drop.
  • Check for an open circuit, high resistance connection, or a short to voltage on the signal wire with the sensor connector disconnected, as a circuit-high code is most often caused by an open signal circuit, a poor ground connection, or a short to a voltage source.
  • Confirm the PCM is supplying proper reference voltage at the sensor connector with the sensor disconnected; absence of reference voltage points to a PCM-side wiring fault or PCM internal issue rather than sensor failure.

Step 3: Resolution & Reset Process

  • Repair or replace any damaged wiring, corroded terminals, or faulty connectors identified during testing, using proper weatherproof splice/solder techniques and OEM-spec connector pins.
  • Replace the intake air temperature sensor if it fails resistance or live data verification against the service manual specification.
  • Clean the connector contacts with approved electrical contact cleaner and apply dielectric grease to the terminals upon reassembly to prevent future corrosion-related circuit faults.
  • Clear the DTC with a scan tool and perform a complete drive cycle as specified in the service information, ensuring the vehicle is driven through varying load, speed, and engine temperature conditions to allow the PCM to run its IAT circuit monitor.
  • Verify the IAT live data reads correctly and tracks realistically at cold start and climbs appropriately toward underhood temperature at operating temperature, and confirm no pending or repeat codes using the scan tool’s readiness monitor status.

📦 Parts, Labor, and Budget Estimates

Required Components/Software:

  • Intake air temperature sensor (standalone or integrated MAP/MAF assembly depending on platform): OEM Mopar part number to be confirmed via VIN/parts lookup for exact year, model, and engine.
  • Connector or pigtail repair kit (if required): aftermarket universal Metri-Pack/Weather-Pack style repair kit or OEM Mopar connector repair kit as applicable.
  • Dielectric grease and electrical contact cleaner: one small application tube and one aerosol can typically sufficient per repair.
  • Scan tool capable of bi-directional OBD-II generic and enhanced Chrysler/Dodge-specific data streams (e.g., professional-grade scan tools such as Snap-on, Autel, Launch, or OEM-level software such as Chrysler wiTECH for dealer-level diagnostics and any required module resets).

Average Component Price:

  • Intake air temperature sensor: approximately $20–$85 USD depending on whether it is a standalone sensor or integrated into a MAP/MAF assembly.
  • Wiring repair materials (connector, terminals, splice supplies): approximately $15–$60 USD.
  • Consumables and shop supplies (contact cleaner, dielectric grease, shop rags): approximately $5–$15 USD.

Estimated Labor Hours:

  • Diagnosis and verification: 0.5–1.0 hour.
  • Sensor replacement or wiring repair: 0.3–1.0 hour (standalone sensor replacement is quick; integrated MAP/MAF sensor or harness repair in a congested area takes longer).
  • Clear, drive cycle, and final verification: 0.2–0.5 hour (plus actual drive cycle time, which does not require dedicated shop labor if performed during road test).
  • Total estimated labor: approximately 1.0–2.5 hours, with total out-the-door cost (parts and labor combined) typically ranging from $120–$350 USD depending on shop labor rate and whether wiring repair or dealer-level diagnostic software access is required.