how to troubleshoot B1491 code in Volkswagen Golf Seventh Generation (2013-2020)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle's battery to ensure safety while working on the electrical components.

2. Inspect and Replace Refrigerant Pressure Sensor

• Tools Required: Socket set, multimeter, refrigerant manifold gauge set
• Sub-steps:
  1. Locate the refrigerant pressure sensor, typically found on the AC line.
  2. Disconnect the electrical connector from the sensor.
  3. Use the socket set to remove the old refrigerant pressure sensor.
  4. Install the new refrigerant pressure sensor by threading it into the AC line and tightening to manufacturer torque specifications (usually around 20 Nm).
  5. Reconnect the electrical connector to the new sensor.

3. Recharge AC System

• Tools Required: Refrigerant manifold gauge set, refrigerant can
• Sub-steps:
  1. Connect the manifold gauge set to the AC service ports.
  2. Follow the manufacturer’s guidelines to add refrigerant to the system until the correct pressure is reached.
  3. Monitor the gauges to ensure proper operation and no leaks during the recharge.

4. Clear Codes and Test

• Tools Required: OBD-II scanner
• Sub-steps:
  1. Reconnect the vehicle's battery.
  2. Use the OBD-II scanner to clear the B1491 code from the system.
  3. Start the vehicle and run the AC to verify proper operation.