How to Fix P1242 Fuel Pump Secondary Circuit Malfunction

Introduction

If you’re experiencing a P1242 Fuel Pump Secondary Circuit Malfunction error code, it means that there’s an issue with the fuel pump secondary circuit. This can be caused by a variety of factors, including a faulty fuel pump relay, damaged wiring, or a malfunctioning fuel pump. In this article, we’ll go over the steps you can take to fix this issue and get your car back on the road.

Step 1: Check the Fuel Pump Relay

The first thing you should do when you encounter a P1242 error code is to check the fuel pump relay. This relay is responsible for sending power to the fuel pump, and if it’s faulty, it can cause the secondary circuit to malfunction. To check the relay, locate it in your car’s fuse box and remove it. Inspect the relay for any signs of damage or wear, such as burnt contacts or a cracked casing. If the relay looks damaged, replace it with a new one.

Step 2: Inspect the Wiring

If the fuel pump relay is not the issue, the next step is to inspect the wiring. Look for any signs of damage or wear, such as frayed wires or corroded connections. If you find any damaged wiring, repair or replace it as necessary. It’s also a good idea to check the wiring connections to ensure they’re secure and tight.

Step 3: Test the Fuel Pump

If the fuel pump relay and wiring are both in good condition, the next step is to test the fuel pump itself. To do this, you’ll need a fuel pressure gauge. Connect the gauge to the fuel system and turn on the ignition. The gauge should read between 30 and 45 psi. If the pressure is too low, it could indicate a faulty fuel pump. In this case, you’ll need to replace the fuel pump.

Step 4: Replace the Fuel Pump

If you’ve determined that the fuel pump is the issue, you’ll need to replace it. This can be a complex process, so it’s important to follow the manufacturer’s instructions carefully. Start by disconnecting the battery and relieving the fuel pressure. Then, remove the fuel pump from the fuel tank and replace it with a new one. Reconnect the battery and test the fuel pressure again to ensure that the new pump is working properly.

Step 5: Clear the Error Code

Once you’ve fixed the issue, you’ll need to clear the P1242 error code from your car’s computer. To do this, you’ll need an OBD-II scanner. Connect the scanner to your car’s OBD-II port and follow the instructions to clear the code. Once the code has been cleared, start your car and ensure that the error code does not reappear.

Conclusion

Fixing a P1242 Fuel Pump Secondary Circuit Malfunction error code can be a complex process, but by following these steps, you can diagnose and fix the issue. Remember to always follow the manufacturer’s instructions carefully and take safety precautions when working on your car.

FAQs

1. Can I drive my car with a P1242 error code?

It’s not recommended to drive your car with a P1242 error code, as it can indicate a serious issue with your fuel system. If you must drive your car, do so with caution and get it to a mechanic as soon as possible.

2. How much does it cost to fix a P1242 error code?

The cost to fix a P1242 error code can vary depending on the cause of the issue. If it’s a simple fix, such as a faulty relay, it may only cost a few dollars. However, if the fuel pump needs to be replaced, it can cost several hundred dollars.

3. How can I prevent a P1242 error code from occurring?

To prevent a P1242 error code from occurring, it’s important to maintain your car’s fuel system. This includes regular maintenance, such as changing the fuel filter and keeping the fuel tank clean. It’s also important to address any issues with the fuel system as soon as they arise, to prevent them from becoming more serious.