Engine-Codes - Mercedes-Benz - P0126 Mercedes-Benz

P0126 Mercedes-Benz Code - Insufficient Coolant Temperature for Stable Operation

- Code Popularity: 7,309 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 2/3
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What are the Possible Causes of the DTC P0126 Mercedes-Benz?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Low engine coolant level
  • Leaking or stuck open thermostat
  • Faulty Engine Coolant Temperature (ECT) sensor
  • Engine Coolant Temperature (ECT) sensor harness is open or shorted
  • Engine Coolant Temperature (ECT) sensor electrical circuit poor connection
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How to Fix the DTC P0126 Mercedes-Benz?

Check 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.

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What is the Cost to Diagnose the Code?

Labor: 1.0

The cost to diagnose the P0126 Mercedes-Benz code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.

When is the Code Detected?

The voltage sent to Engine Control Module (ECM) from the sensor is not practical, even when some time has passed after starting the engine.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

What Does the P0126 Mercedes-Benz Code Mean?

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 the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.

P0126 Mercedes-Benz Code - Insufficient Coolant Temperature for Stable Operation

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