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P1119 – OBD-II DTC

OBD-II DTC P1119 – Engine Coolant Temperature (ECT) Sensor Circuit Intermittent Low Voltage/IAT – B Circuit Low Input

DTC P1119 meaning

DTC P1119 refers to a diagnostic trouble code indicating an intermittent low voltage condition in the Engine Coolant Temperature (ECT) sensor circuit. This code can also relate to the Intake Air Temperature (IAT) sensor circuit, suggesting a low input signal. The ECT sensor is crucial for monitoring the engine’s temperature, which helps the engine control module (ECM) adjust fuel delivery and ignition timing for optimal performance.

DTC P1119 symptoms

Common symptoms associated with DTC P1119 may include:

  • Check Engine Light (CEL) illuminated
  • Engine overheating or running too cold
  • Poor fuel economy
  • Rough idling or stalling
  • Inconsistent engine performance

DTC P1119 causes

Several factors can trigger DTC P1119, including:

  • Faulty ECT sensor
  • Wiring issues, such as shorts or open circuits
  • Corroded or loose connectors
  • Faulty ECM
  • Issues with the IAT sensor

DTC P1119 seriousness

DTC P1119 can be serious as it affects the engine’s ability to regulate temperature effectively. If left unaddressed, it may lead to:

  • Engine overheating
  • Increased emissions
  • Potential engine damage
  • Poor vehicle performance

How to diagnose DTC P1119

To diagnose DTC P1119, follow these steps:

  1. Use an OBD-II scanner to confirm the presence of the code.
  2. Inspect the ECT and IAT sensor wiring and connectors for damage or corrosion.
  3. Test the ECT sensor with a multimeter to check for proper resistance values.
  4. Check the voltage supply to the ECT sensor while the engine is running.
  5. Examine the ECM for any signs of failure or malfunction.

How to fix DTC P1119 step-by-step instructions

To fix DTC P1119, follow these steps:

  1. Repair or replace any damaged wiring or connectors related to the ECT and IAT sensors.
  2. Replace the faulty ECT sensor if testing indicates it is not functioning correctly.
  3. Ensure the ECM is functioning properly replace it if necessary.
  4. Clear the DTC using an OBD-II scanner.
  5. Test drive the vehicle to ensure the code does not return.

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