P1243 – OBD-II DTC

OBD-II DTC P1243 – Fuel Pump Secondary Circuit Malfunction

DTC P1243 meaning

DTC P1243 refers to a malfunction in the fuel pump secondary circuit. This code indicates that the Engine Control Module (ECM) has detected an issue with the secondary circuit of the fuel pump, which is responsible for providing additional fuel pressure to the engine under certain conditions. The secondary circuit is typically activated during high-demand situations, such as acceleration or heavy load, to ensure optimal engine performance.

DTC P1243 symptoms

Common symptoms associated with DTC P1243 may include:

• Engine stalling or hesitation during acceleration
• Reduced engine power or performance
• Difficulty starting the engine
• Check Engine Light (CEL) illuminated
• Increased fuel consumption

DTC P1243 causes

Several factors can lead to the triggering of DTC P1243, including:

• Faulty fuel pump relay
• Wiring issues or short circuits in the fuel pump circuit
• Defective fuel pump
• Faulty ECM or software issues
• Clogged fuel filter or fuel lines

DTC P1243 seriousness

DTC P1243 can be considered serious as it may lead to engine performance issues, including stalling or reduced power. If left unaddressed, it can result in further damage to the fuel system or engine components. It is advisable to diagnose and repair the issue promptly to maintain vehicle reliability and safety.

How to diagnose DTC P1243

To diagnose DTC P1243, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1243 code.
2. Inspect the fuel pump relay and wiring for any visible damage or corrosion.
3. Check the fuel pump operation by listening for its activation when the ignition is turned on.
4. Test the fuel pump circuit for continuity and proper voltage using a multimeter.
5. Examine the fuel filter and lines for clogs or restrictions.
6. Check the ECM for any software updates or faults.

How to fix DTC P1243 step-by-step instructions

To fix DTC P1243, follow these step-by-step instructions:

1. Clear the DTC using an OBD-II scanner.
2. Inspect and replace the fuel pump relay if faulty.
3. Repair or replace any damaged wiring in the fuel pump circuit.
4. Test and replace the fuel pump if it is not functioning correctly.
5. Replace the fuel filter if clogged.
6. Recheck the system for any remaining issues and ensure all connections are secure.

How to erase DTC P1243

To erase DTC P1243, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the codes.
5. Disconnect the scanner and start the engine to ensure the code does not return.

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