what does code B1650 mean for Toyota Highlander Fourth Generation (2020-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to prevent electrical shorts.
• Allow the engine to cool down before beginning work.

2. Inspect and Replace Fuses/Relays

• Tools Required: Fuse puller, multimeter
• Locate the A/C fuse and relay in the fuse box.
• Use a multimeter to check for continuity in the fuse. Replace if blown.
• Check the relay operation by swapping with a known good relay; replace if faulty.

3. A/C Switch Inspection

• Tools Required: Screwdriver set
• Remove the dashboard panel covering the A/C controls.
• Disconnect the A/C switch connector and inspect for corrosion or loose connections.
• Test the A/C switch operation with a multimeter and replace if defective.

4. A/C Amplifier Testing

• Tools Required: Multimeter
• Locate the A/C amplifier, usually found near the A/C evaporator.
• Disconnect the amplifier connector and inspect for damage.
• Measure the input voltage and signals at the amplifier; replace if readings are out of specification.

5. Wiring Inspection

• Tools Required: Wire stripper, electrical tape
• Visually inspect the wiring harness connected to the A/C components.
• Look for frayed wires, loose connections, or damage.
• Repair or replace damaged sections of wiring as necessary.

6. Reconnect and Test

• Reconnect all components and wiring.
• Reconnect the vehicle battery.
• Clear the trouble codes using the OBD-II scanner.
• Test the A/C system to confirm proper operation.