P1116 MERCURY – Engine Coolant Temperature Sensor Out of Self-Test Range

P1116 MERCURY Possible Causes

  • Low engine coolant level
  • Faulty Engine Coolant Temperature (ECT) sensor
  • Engine Coolant Temperature (ECT) sensor harness is open or shorted
  • Poor electrical connection in the Engine Coolant Temperature (ECT) sensor circuit
  • Faulty engine coolant thermostat
  • Damaged Powertrain Control Module (PCM)

How to Fix P1116 MERCURY Code?

Start by checking the “possible causes” listed above. Visually inspect the related 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)
Engine Overheating

P1116 MERCURY Meaning

The Engine Coolant Temperature (ECT) sensor is a thermistor device in which resistance changes with temperature. The electrical resistance of a thermistor decreases as the temperature increases, and resistance increases as the temperature decreases. The varying resistance changes 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 the change in the passive sensor’s resistance causes a change in the total current flow. The voltage that drops across a fixed resistor (pull-up 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 ECT measures the engine coolant temperature. The PCM uses the ECT input for fuel control and for cooling fan control. There are 3 types of ECT sensors; threaded, push-in, and twist-lock. The ECT sensor is located in an engine coolant passage.

P1116 MINI – Mass or Volumetric Air Flow Circuit Range / Performance Problem, Row 2

P1116 MINI Possible Causes

  • Faulty mass air flow sensor
  • Mass air flow sensor harness is open or shorted
  • Poor electrical connection in mass air flow sensor circuit

How to Fix P1116 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)

P1116 MINI Meaning

Mass or Volume Air Flow Circuit Range/Performance Problem Bank 2 is the generic description for P1116 Mini code, but the manufacturer may have a different description for your vehicle model and year. Currently we don’t have further information about the P1116 Mini OBDII code.

P1116 SCION – Coolant Temperature Sensor Circuit for Coolant Heat Storage System

P1116 SCION Possible Causes

  • Low engine coolant level
  • Faulty Engine Coolant Temperature (ECT) sensor
  • Engine Coolant Temperature (ECT) sensor harness is open or shorted
  • Poor electrical connection in Engine Coolant Temperature (ECT) sensor circuit
  • Faulty engine coolant thermostat

How to Fix P1116 SCION Code?

Start by checking the “possible causes” listed above. Visually inspect the related 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)

P1116 SCION Meaning

The battery circuit of the coolant temperature sensor for the coolant heat storage system is the generic description for P1116 Scion code, but the manufacturer may have a different description for your specific vehicle model and year. Currently, we don’t have additional information about the OBDII P1116 Scion code.

P1116 SUBARU – Low Input of Engine Torque Control Cutoff Signal Circuit

How to Fix P1116 SUBARU 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)

P1116 SUBARU Meaning

The low input of the engine torque control cut signal circuit is the generic description of Subaru code P1116, but the manufacturer may have a different description for your vehicle model and year. Currently, we do not have additional information about the OBDII P1116 Subaru code.

P1116 SUZUKI – Engine Coolant Temperature Circuit Performance at Engine Soak

P1116 SUZUKI Possible Causes

  • Low engine coolant level
  • Faulty Engine Coolant Temperature (ECT) sensor
  • Engine Coolant Temperature (ECT) sensor harness is open or shorted
  • Poor electrical connection in the Engine Coolant Temperature (ECT) sensor circuit
  • Faulty engine coolant thermostat

How to Fix P1116 SUZUKI Code?

Start by checking the “possible causes” listed above. Visually inspect the related 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 engine service warning light soon)

P1116 SUZUKI Meaning

The Engine Coolant Temperature (ECT) sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the Engine Control Module (ECM). The modified signal returns to the ECM as an engine coolant temperature input. The sensor uses a thermistor sensitive to temperature change. The electrical resistance of the thermistor decreases as temperature increases.

P1116 TOYOTA – Coolant temperature sensor circuit for coolant heat storage system

P1116 TOYOTA Possible Causes

  • Low engine coolant level
  • Faulty Engine Coolant Temperature (ECT) sensor
  • Engine Coolant Temperature (ECT) sensor harness is open or shorted
  • Poor electrical connection in Engine Coolant Temperature (ECT) sensor circuit
  • Faulty engine coolant thermostat

How to Fix P1116 TOYOTA Code?

Start by checking the “Possible Causes” listed above. Visually inspect the related 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 engine service warning light soon)

P1116 TOYOTA Meaning

The battery circuit of the coolant temperature sensor for the coolant heat storage system is the generic description of the P1116 Toyota code, but the manufacturer may have a different description for your specific vehicle model and year. Currently, we don’t have more information about the Toyota P1116 OBDII code.

P1116 VOLKSWAGEN – Open HO2S Heater Circuit, Bank 1 Sensor 1

P1116 VOLKSWAGEN Possible Causes

  • Faulty HO2 sensor, Bank 1 Sensor 1
  • HO2 Sensor Bank 1 Sensor 1 wiring open or short circuit
  • HO2 Sensor, Bank 1, Sensor 1 circuit, poor electrical connection

How to Fix P1116 VOLKSWAGEN 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)

P1116 VOLKSWAGEN Meaning

HO2S Heater Circuit Open, Bank 1 Sensor 1 is the generic description for Volkswagen P1116 code, but the manufacturer may have a different description for your vehicle model and year. Currently, we don’t have further information about Volkswagen OBDII P1116 code.

P1117 – Intermittent Engine Coolant Temperature Sensor

Repair Procedure:

  1. Preparation and Safety:

    • Cold engine (risk of burns and pressure in the cooling circuit).

    • Basic tools + digital multimeter (DMM).

    • Vehicle-specific technical documentation (electrical diagrams, ECT sensor resistance/voltage values).

  2. Visual Inspection (Priority):

    • Coolant Level: Check and top up if necessary. A low level can expose the ECT sensor and distort its reading.

    • Physical inspection of cables and connectors:

      • Disconnect the ECT sensor connector and the PCM connector (if accessible).

      • Look for corrosion, bent/broken/retracted pins, frayed or melted wires, damaged insulation. Clean corrosion with an electrical contact cleaner.

      • Check the tightness of the connector to the sensor (damaged O-ring?).

    • ECT Sensor Inspection: Coolant leak at the threads or seal? Physical damage?

  3. ECT Sensor Test (Resistance – Cold & Hot Engine):

    • Disconnect the sensor’s electrical connector.

    • Measure the resistance between the sensor terminals with the multimeter in Ohms (Ω).

    • Cold Engine: High resistance (e.g., several kΩ at 20°C – check specific values in the technical documentation).

    • Engine at Operating Temperature: Much lower resistance (e.g., a few hundred Ω at 90°C – check the documentation).

    • Compare your measurements to the manufacturer’s specific values. Infinite resistance (open circuit) or zero (short circuit) indicates a faulty sensor. A value outside specifications also indicates a defective sensor.

  4. Electrical Circuit Test:

    • Power Supply (VRef – often 5V):

      • Turn ignition ON without starting.

      • Reconnect the connector to the sensor or use a backprobe pin.

      • Measure the voltage between the VRef wire (usually a light-colored wire, check diagram) and ground. Expected: ~5V. If 0V: short to ground or open circuit between PCM and sensor, or faulty PCM. If 12V: short to battery voltage.

    • Ground:

      • Ignition ON.

      • Measure the voltage between the sensor’s ground wire (usually a black or dark wire) and the chassis ground. Expected: ~0V. If high voltage: poor ground circuit (corrosion, loose connection).

    • Signal:

      • Ignition ON.

      • Measure the voltage between the sensor’s signal wire and ground. Cold engine: High voltage (e.g., 3-4.5V). Hot engine: Low voltage (e.g., 0.5-1.5V). Compare to specifications.

      • A constant voltage (e.g., 5V, 0V, or VRef) or a value outside specifications indicates a circuit or sensor problem.

    • Continuity/Isolation Test:

      • Ignition OFF.

      • Check continuity (≈0Ω) for each wire between the ECT connector and the PCM connector (VRef, Signal, Ground).

      • Check for the absence of short circuits (∞Ω) between each wire and ground or +12V.

  5. Thermostat Check:

    • A thermostat stuck open prevents the engine from reaching its normal temperature, potentially generating a code related to a persistent “abnormally low” ECT reading.

    • Monitor the engine temperature rise on the dashboard or with a diagnostic tool. A very slow rise or a maximum temperature that is too low (<80°C while driving) is suspicious.

    • A physical test of the thermostat (removing it and immersing it in boiling water to see if it opens) is more conclusive.

  6. PCM Diagnosis (Last Resort):

    • PCMs rarely fail. Consider this cause only if:

      • All other checks are OK (circuits, power supplies, ground, sensor).

      • The fault persists after replacing the sensor.

      • Thorough circuit tests (with a precise diagram) point to the PCM.

    • Before condemning the PCM, check the quality of the connections and the PCM’s own ground.

Summary of Causes & Corrective Actions:

Possible Cause Corrective Action
Low fluid level Top up coolant, find and repair leak.
Faulty ECT sensor Replace ECT sensor. Use appropriate seal if necessary.
Open/shorted wiring harness Repair or replace damaged wire(s). Clean/tighten connections.
Poor electrical connection Clean contacts, straighten/re-crimp pins, replace connector.
Faulty thermostat Replace thermostat. Properly bleed the cooling circuit.
Damaged PCM Diagnose thoroughly before! Replace or reprogram PCM.

After Repair:

  1. Clear the fault code with a diagnostic tool.

  2. Perform a drive cycle to verify that the fault does not reappear and that the engine temperature behaves normally.

  3. Check that the Malfunction Indicator Lamp (MIL) no longer illuminates.

This systematic approach, starting with the simplest and most common checks, allows for effective diagnosis and repair of the P1117 code.

P1117 AUDI – HO2S Heater Short to Ground, Bank 1 Sensor 2

P1117 AUDI Possible Causes

  • Faulty HO2 sensor, Bank 1 Sensor 2
  • HO2 Sensor Bank 1 Sensor 2 harness is open or shorted
  • HO2 Sensor Bank 1 Sensor 2 circuit poor electrical connection

How to Fix P1117 AUDI 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)

P1117 AUDI Meaning

HO2S Heater Circuit Short to Ground, Bank 1 Sensor 2 is the generic description for Audi P1117 code, but the manufacturer may have a different description for your vehicle model and year. Currently, we don’t have further information about the Audi P1117 OBDII code.

P1117 BMW – Mass or Volume Air Flow Circuit Low Input, Row 2

P1117 BMW Possible Causes

  • Faulty mass air flow sensor
  • Mass air flow sensor harness is open or shorted
  • Poor electrical connection in mass air flow sensor circuit

How to Fix BMW P1117 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)

P1117 BMW Meaning

The mass or volume air flow circuit bank 2 input is the generic description for BMW P1117 code, but the manufacturer may have a different description for your vehicle model and year. Currently, we don’t have more information about the P1117 BMW OBDII code.