Description:

This error code indicates that the voltage at the coolant temperature sensor input is below 0.25 volts, which typically signals a short circuit to ground. This condition prevents the sensor from providing accurate temperature data, affecting engine management.

Reaction:

When this error is detected, the control software will limit or disable certain functions to protect the engine from incorrect temperature readings. This safeguard helps maintain safe operating conditions.

Recommendations:

Inspect Sensor Wiring:

• Check the wiring harness connected to the coolant temperature sensor for any signs of damage, disconnection, or corrosion.
• Repair or replace any damaged wiring.

Test Sensor Connector:

• Ensure the sensor connector is properly seated and free from debris or corrosion.
• Clean or replace the connector if necessary.

Measure Sensor Voltage:

• Use a multimeter to measure the voltage at the coolant temperature sensor. Ensure it is above 0.25 volts and within the manufacturer-specified range.

Check for Ground Shorts:

• Inspect the wiring for any signs of shorts to ground. This includes checking for any exposed wires that may be touching grounded metal surfaces.

Replace Faulty Sensor:

• If the sensor itself is determined to be faulty, replace it with a new, manufacturer-approved part.

Verify ECU Connections:

• Ensure that all connections to the Engine Control Unit (ECU) are secure and free from corrosion.

Note:

Regular maintenance and inspection of sensor wiring and connections are crucial for accurate temperature monitoring. Promptly addressing any signs of wear or damage can prevent issues with low voltage readings and ensure reliable engine performance.