P0126 - INSUFFICIENT COOLANT TEMPERATURE FOR STABLE OPERATION

The vehicles are equipped with a Engine Coolant Temperature (ECT) whose signal is sent to the PCM (Powertrain Control Module) to optimize the operation of the vehicle.

For the correct operation of the engine, it is necessary that it reaches a particular temperature range. If in a period of time the vehicle does not reach this operating temperature, the DTC code P0126 OBDII is set, so the warning or Check Engine light will illuminate.

It should be noted that this code will not be set immediately after the engine starts. It is only set after a period of time, which has been programmed by the PCM. Although that time period varies by manufacturer, ambient temperatures can influence that period.

• MIL light on (Engine malfunction).
• Increases fuel consumption.

The reasons for configuring the diagnostic code P0126 OBD2 are:

• The engine coolant level may be too low.
• Thermostat may be defective.
• ECT Sensor connector electrical connections may be faulty due to bad wires or connectors.
• The ECT Sensor (Engine Coolant Temperature Sensor) is damaged.

The steps to follow to solve the problems of the fault code P0126 OBDII are:

• The first step is to consult the TSB (Technical Service Bulletins).
• Check the cooling fan, make sure it is working properly. It should be turned on and off as needed. If this is not the case, you should make the necessary repairs.
• Check the engine coolant level, if it is too low you should fix it.
• With a scanner observe the live data of the ECT Compare with the manufacturer's specifications.
• Inspect the thermostat to make sure it is in good condition, repair or replace.
• Check all the cables of the ECT Sensor, if you find inconsistencies you should repair them.
• Replace the ECT