P2181 - COOLING SYSTEM PERFORMANCE

The Powertrain Control Module (PCM) constantly monitors the engine temperature through the cooling system while the engine is running. This process is done to determine the time in which the engine is cold, in that condition the air/fuel mixture is rich and allows the engine to run smoothly as it warms up. Low engine temperature is also detected which can affect the efficiency of the exhaust gases. And additionally, it is determined if the engine operating temperature is excessively high, which can result in overheating of the engine.

If the engine temperature reading changes faster than the PCM considers normal, the DTC code P2181 OBD2 is set and the Check Engine light illuminates.

• The engine temperature indicator shows a higher or lower temperature than normal.
• Engine overheating.
• Higher fuel consumption.

The reasons for the establishment of fault code P2181 OBDII are

• The Coolant Temperature Sensor (ECT) connector may be corroded.
• The connection between the ECT Sensor and the PCM may be poor.
• The ECT Sensor may be defective.
• Damaged system wiring or connector.
• Perhaps the thermostat is stuck in the open or closed position.
• A low level of the coolant.

The steps for solving the problems associated with the diagnostic code P2181 OBD2 are

• Check that the engine coolant level is adequate. If there is a lack of coolant, check there are no leaks.
• Check that the radiator fan is working properly. Change it if necessary.
• Make sure the water pump does not leak. Repair as needed.
• Verify the operation of the Coolant Temperature Sensor. Use a DVOM and check the resistance of the sensor. If the engine is cold, the resistance is high and as the engine temperature increases, the resistance decreases. If it reads erratically, check its circuit or change the sensor.
• If the engine is functioning properly but the error code P2181 still appears, replace the thermostat.