what does code B1242 mean for my Toyota Highlander Third Generation (2014-2019)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to ensure safety during the repair process.

2. Inspect and Replace Fuses/Relays

• Locate the A/C fuses and relays in the engine compartment fuse box.
• Remove any blown fuses and replace them with new ones of the same amperage.
• Test relays by swapping with a similar one to see if the A/C functions properly.

3. Repair or Replace Wiring and Connectors

• Visually inspect the wiring and connectors from the A/C ECU to the compressor and other components.
• Repair any frayed or damaged wires using electrical tape or heat shrink tubing.
• If connectors show signs of corrosion, clean them with electrical contact cleaner or replace them if necessary.

4. Test A/C Compressor

• Reconnect the battery and start the engine.
• Turn on the A/C and listen for the compressor engagement.
• If the compressor does not engage, check its power supply and ground connections.

5. A/C Pressure Check

• Connect the manifold gauge set to the A/C service ports.
• Check the low and high-pressure readings against the manufacturer's specifications.
• If the readings are outside acceptable limits, the system may need refrigerant recharge or repair.

6. Clear Codes and Test

• Use the OBD-II scanner to clear the B1242 code from the ECU.
• Take the vehicle for a test drive to ensure the A/C system operates correctly and verify that the code does not return.