P1112 HONDA – Intermittent Low Voltage in Intake Air Temperature Sensor Circuit

P1112 HONDA Possible Causes

  • Faulty intake air temperature sensor
  • Intake air temperature sensor harness is open or shorted
  • Poor electrical connection in intake air temperature sensor circuit

How to Fix P1112 HONDA Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Illuminated engine light (or service engine soon warning light)

P1112 HONDA Meaning

The intake air temperature (IAT) sensor is integrated into the mass air flow sensor or in some vehicles mounted on the air filter housing. The sensor detects the intake air temperature and sends a signal to the engine control module (ECM). The temperature sensing unit uses a thermistor that is sensitive to temperature changes. The electrical resistance of the thermistor decreases in response to increasing temperature. The intake air temperature signal is used as input for various vehicle systems.

P1112 HYUNDAI – Manifold Differential Pressure Sensor

P1112 HYUNDAI Possible Causes

  • Faulty intake air temperature sensor
  • Intake air temperature sensor harness is open or shorted
  • Poor electrical connection in the intake air temperature sensor circuit

How to Fix P1112 HYUNDAI Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Illuminated check engine light (or service engine soon warning light)

P1112 HYUNDAI Meaning

The intake air temperature (IAT) sensor is integrated into the mass air flow sensor or in some vehicles mounted on the air filter housing. The sensor detects the intake air temperature and sends a signal to the engine control module (ECM). The temperature sensing unit uses a thermistor that is sensitive to temperature changes.

The electrical resistance of the thermistor decreases in response to increasing temperature. The intake air temperature signal is used as an input for various vehicle systems.

P1112 ISUZU – Intermittent Low Voltage in Intake Air Temperature Sensor Circuit

P1112 ISUZU Possible Causes

  • Faulty intake air temperature sensor
  • Intake air temperature sensor harness is open or shorted
  • Poor electrical connection in the intake air temperature sensor circuit

How to Fix P1112 ISUZU Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Illuminated engine light (or service engine soon warning light)

P1112 ISUZU Meaning

The intake air temperature (IAT) sensor is integrated into the mass air flow sensor or in some vehicles mounted on the air filter housing. The sensor detects intake air temperature and sends a signal to the engine control module (ECM). The temperature sensing unit uses a thermistor that is sensitive to temperature changes. The electrical resistance of the thermistor decreases in response to increasing temperature. The intake air temperature signal is used as input for various vehicle systems

P1112 JEEP – Intermittent low voltage in the intake air temperature sensor circuit

P1112 JEEP Possible Causes

  • Faulty intake air temperature sensor
  • Intake air temperature sensor harness is open or shorted
  • Poor electrical connection in the intake air temperature sensor circuit

How to Fix JEEP P1112 Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Illuminated engine light (or service engine soon warning light)

P1112 JEEP Meaning

The intake air temperature (IAT) sensor is integrated into the mass air flow sensor or in some vehicles mounted on the air filter housing. The sensor detects the intake air temperature and sends a signal to the engine control module (ECM). The temperature sensing unit uses a thermistor that is sensitive to temperature changes. The electrical resistance of the thermistor decreases in response to increasing temperature. The intake air temperature signal is used as input for various vehicle systems.

P1112 KIA – Intermittent Low Voltage in Intake Air Temperature Sensor Circuit

P1112 KIA Possible Causes

  • Faulty intake air temperature sensor
  • Intake air temperature sensor harness is open or shorted
  • Poor electrical connection in the intake air temperature sensor circuit

How to Fix P1112 KIA Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Illuminated engine light (or service engine soon warning light)

P1112 KIA Meaning

The intake air temperature (IAT) sensor is integrated into the mass air flow sensor or in some vehicles mounted on the air filter housing. The sensor detects the intake air temperature and sends a signal to the engine control module (ECM). The temperature sensing unit uses a thermistor that is sensitive to temperature change. The electrical resistance of the thermistor decreases in response to increasing temperature. The intake air temperature signal is used as input for various vehicle systems.

P1112 LINCOLN – Intermittent Intake Air Temperature Sensor Condition

P1112 LINCOLN Possible Causes

  • Faulty intake air temperature sensor
  • Intake air temperature sensor harness is open or shorted
  • Poor electrical connection in the intake air temperature sensor circuit
  • Damaged Powertrain Control Module (PCM)

How to Fix P1112 LINCOLN Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

What Does It Mean?

Before replacing the mass air flow sensor, try replacing the air filter and cleaning the air flow sensor with mass air flow sensor cleaner. Reset the code and drive the vehicle. If the code returns, it may be necessary to replace the mass air flow sensor. Monitor the IAT on a scan tool. Look for sudden changes in the reading when the harness is shaken or the sensor is tapped.

Possible Symptoms

Check Engine Light illuminated (or Service Engine Soon Warning Light)

P1112 LINCOLN Meaning

The IAT sensor is a thermistor device in which resistance changes with temperature. The electrical resistance of a thermistor decreases as temperature increases and resistance increases as temperature decreases. The variable resistance affects the voltage drop across the sensor terminals and provides electrical signals to the Powertrain Control Module (PCM) corresponding to the temperature.
Thermistor-type sensors are considered passive sensors. A passive sensor is connected to a voltage divider network so that the change in the passive sensor’s resistance causes a change in the total current flow. The voltage that drops across a fixed resistor in series with the sensor resistance determines the voltage signal to the PCM. This voltage signal is equal to the reference voltage minus the voltage drop across the fixed resistor.

The IAT sensor provides air temperature information to the PCM. The PCM uses air temperature information as a correction factor in the calculation of fuel flow, spark, and air.

The IAT sensor provides faster response time to temperature change than the ECT or CHT sensor.

Currently, there are 2 types of IAT sensors used, a standalone, non-integrated type and an integrated type. Both types function the same way, but the integrated type is incorporated into the mass air flow sensor (MAF) instead of being a standalone sensor.

P1112 MAZDA – Intermittent low voltage in intake air temperature sensor circuit

MAZDA Code P1112: Causes, Symptoms, and Solutions

Meaning of Code P1112

Code P1112 on a Mazda indicates a problem with the Intake Air Temperature (IAT) sensor or its circuit. This sensor measures the temperature of the air entering the engine and sends a signal to the Engine Control Module (ECM).

  • Operation: The IAT sensor uses a thermistor whose electrical resistance decreases as the temperature increases.
  • Location: Integrated into the Mass Air Flow (MAF) sensor or mounted on the air filter housing.
  • Impact: The ECM uses this data to adjust the air-fuel mixture, ignition timing, and other critical parameters.

Common Symptoms

  • Check Engine Light illuminated (or warning message).
  • Unstable idle or vibrations.
  • Increased fuel consumption.
  • Reduced performance (weak acceleration).
  • Hard starting in cold weather.

Possible Causes

  1. Faulty IAT Sensor:
  • Damaged or degraded thermistor.
  • Cut or oxidized internal wiring.
  1. Electrical Problems:
  • Short circuit or open circuit in the sensor harness.
  • Corroded, loose, or poorly secured connectors.
  1. ECM Failure:
  • Programming error or hardware failure (rare).

Diagnostic Procedures

  1. Visual Inspection:
  • Locate the IAT sensor (near the air filter or integrated into the MAF).
  • Check the harness and connectors for exposed wires, damaged insulation, or corrosion.
  1. IAT Sensor Test:
  • Disconnect the connector and measure the resistance with a multimeter.
    • Expected Values:
    • ~2,000 to 3,000 Ω at 20°C.
    • ~200 to 400 Ω at 80°C.
  • Compare with Mazda specifications.
  1. Electrical Circuit Check:
  • Test the supply voltage (5 V with ignition on).
  • Check continuity between the sensor and the ECM.

Recommended Solutions

  1. Replace the Faulty IAT Sensor:
  • Choose a compatible or OEM sensor (e.g., Denso, Hitachi).
  • Clean the mounting area to prevent air leaks.
  1. Repair the Electrical Harness:
  • Repair damaged wires with waterproof solder joints.
  • Replace oxidized or broken connectors.
  1. Reset the ECM:
  • Clear the P1112 code with an OBD-II scanner after repair.
  • If the code persists, consider ECM reprogramming.

Important Precautions

  • Disconnect the battery before any electrical work.
  • Avoid contaminants: Clean the air filter housing to prevent incorrect readings.
  • Test the MAF sensor: If the IAT sensor is integrated into the MAF, also check its condition.

Estimated Costs

  • IAT Sensor: €30 to €100.
  • Labor: 0.5 to 1 hour (€40 to €100).
  • MAF Replacement (if integrated): €100 to €300.

Conclusion

Code P1112 on a Mazda often signals a simple problem like a dirty IAT sensor or a faulty connector. Ignoring this code can lead to an unbalanced air-fuel mixture, eventually damaging the catalytic converter or increasing engine wear. If basic checks do not resolve the issue, consult a certified Mazda mechanic for a thorough diagnosis, especially if symptoms like high fuel consumption persist.

P1112 MERCURY – Intermittent Intake Air Temperature Sensor Condition

P1112 MERCURY Possible Causes

  • Faulty intake air temperature sensor
  • Intake air temperature sensor harness is open or shorted
  • Poor electrical connection in the intake air temperature sensor circuit
  • Damaged powertrain control module (PCM)

How to Fix P1112 MERCURY Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

What Does It Mean?

Before replacing the mass air flow sensor, try replacing the air filter and cleaning the air flow sensor with mass air flow sensor cleaner. Reset the code and drive the vehicle. If the code returns, the mass air flow sensor may need to be replaced. Monitor the IAT on a scan tool. Look for sudden changes in the reading when the harness is shaken or the sensor is tapped.

Possible Symptoms

Check engine light illuminated (or service engine soon warning light)

P1112 MERCURY Meaning

The IAT sensor is a thermistor device in which resistance changes with temperature. The electrical resistance of a thermistor decreases as temperature increases and resistance increases as temperature decreases. The variable resistance affects the voltage drop across the sensor terminals and provides electrical signals to the powertrain control module (PCM) corresponding to temperature.
Thermistor-type sensors are considered passive sensors. A passive sensor is connected to a voltage divider network so that the change in resistance of the passive sensor causes a change in the total current flow. The voltage that drops across a fixed resistor in series with the sensor resistance determines the voltage signal to the PCM. This voltage signal is equal to the reference voltage minus the voltage drop across the fixed resistor.

The IAT sensor provides air temperature information to the PCM. The PCM uses air temperature information as a correction factor in the calculation of fuel, spark, and air flow.

The IAT sensor provides faster response time to temperature change than the ECT or CHT sensor.

Currently, there are 2 types of IAT sensors used, a standalone, non-integrated type and an integrated type. Both types work the same way, but the integrated type is incorporated into the mass air flow (MAF) sensor instead of being a standalone sensor.

P1112 MINI – Engine Coolant Temperature Radiator Output Sensor High Input

P1112 MINI Possible Causes

  • Faulty engine coolant temperature radiator outlet sensor
  • Engine coolant temperature radiator outlet sensor harness is open or shorted
  • Poor electrical connection in engine coolant temperature radiator outlet sensor circuit

How to Fix P1112 MINI Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Check engine light on (or service engine soon warning light)

P1112 MINI Meaning

The engine coolant temperature radiator outlet sensor high input is the generic description for P1112 Mini code, but the manufacturer may have a different description for your vehicle model and year. Currently, we don’t have additional information about P1112 Mini OBDII code.

P1112 PONTIAC – Intermittent Low Voltage in Intake Air Temperature Sensor Circuit

P1112 PONTIAC Possible Causes

  • Faulty intake air temperature sensor
  • Intake air temperature sensor harness is open or shorted
  • Poor electrical connection in the intake air temperature sensor circuit

How to Fix P1112 PONTIAC Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Check engine light illuminated (or service engine soon warning light)

P1112 PONTIAC Meaning

The intake air temperature (IAT) sensor contains a semiconductor device that changes resistance based on temperature (a thermistor). The IAT sensor is mounted in the air intake passage of the engine’s air intake system. The IAT sensor has a signal circuit and a ground circuit. The PCM applies a voltage (approximately 5.0 volts) to the sensor’s signal circuit. The PCM monitors changes in this voltage caused by changes in the sensor’s resistance to determine the intake air temperature.

When the intake air is cold, the sensor’s resistance (thermistor) is high and the PCM’s signal voltage is only slightly lowered across the sensor to ground. The PCM detects a high signal voltage (low temperature). When the intake air is hot, the sensor’s resistance is low and the signal voltage is lowered further. This causes the PCM to detect a low signal voltage (high temperature).