P1620 – Audi DTC

Audi DTC P1620 – Engine coolant temperature signal open/short to B+

DTC P1620 meaning on Audi

The Diagnostic Trouble Code (DTC) P1620 for Audi indicates an issue with the engine coolant temperature signal being open or shorted to B+ (battery positive voltage). This means that the Engine Control Module (ECM) is unable to receive the correct signal from the engine coolant temperature sensor, leading to potential performance and efficiency issues.

Audi DTC P1620 symptoms

Symptoms of DTC P1620 on an Audi may include:

• Engine overheating
• Inaccurate temperature gauge readings
• Decreased fuel efficiency
• Engine misfires or rough idling
• Check Engine Light (CEL) illuminated on the dashboard

Audi DTC P1620 causes

The common causes of DTC P1620 on an Audi are:

• Defective engine coolant temperature sensor
• Wiring issues such as open circuits or short circuits
• Faulty Engine Control Module (ECM)
• Corrosion or poor connections in the coolant temperature sensor circuit

Audi DTC P1620 seriousness

The seriousness of DTC P1620 on an Audi should not be ignored as it can lead to potential engine damage due to overheating or incorrect fuel mixture. It is recommended to address this issue promptly to prevent further complications.

How to diagnose DTC P1620 on Audi

To diagnose DTC P1620 on an Audi, follow these steps:

1. Use an OBD-II scanner to retrieve the fault code and freeze frame data.
2. Inspect the engine coolant temperature sensor and its wiring for any visible damage or corrosion.
3. Check the coolant level and ensure proper circulation in the cooling system.
4. Perform a resistance test on the coolant temperature sensor to verify its functionality.
5. Check for any stored codes related to the coolant temperature sensor circuit.

How to fix DTC P1620 on Audi

To fix DTC P1620 on an Audi, consider the following steps:

1. Replace the engine coolant temperature sensor if it is found to be faulty.
2. Repair any damaged or corroded wiring in the coolant temperature sensor circuit.
3. Clear the fault code using an OBD-II scanner after making the necessary repairs.
4. Perform a test drive to ensure the issue has been resolved and the Check Engine Light does not reappear.

How to erase DTC P1620 on Audi

To erase DTC P1620 on an Audi, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Access the scanner’s menu and select the option to clear fault codes.
3. Confirm the action and wait for the scanner to erase the DTC P1620 code.
4. Disconnect the scanner and start the vehicle to ensure the Check Engine Light is no longer illuminated.

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