P1173 – OBD-II DTC

OBD-II DTC P1173 – Fuel Rail Sensor In-Range Low Failure

DTC P1173 meaning

DTC P1173 refers to a diagnostic trouble code indicating a “Fuel Rail Sensor In-Range Low Failure.” This code is triggered when the Engine Control Module (ECM) detects that the fuel rail pressure sensor is providing a reading that is lower than the expected range. The fuel rail pressure sensor monitors the pressure of the fuel in the rail, which is crucial for optimal engine performance.

DTC P1173 symptoms

Common symptoms associated with DTC P1173 may include:

• Check Engine Light illuminated
• Engine misfires or runs rough
• Decreased engine performance
• Poor fuel economy
• Difficulty starting the engine

DTC P1173 causes

Several factors can lead to the triggering of DTC P1173, including:

• Faulty fuel rail pressure sensor
• Wiring issues or poor connections in the sensor circuit
• Fuel delivery problems, such as a clogged fuel filter or failing fuel pump
• Vacuum leaks affecting fuel pressure
• ECM software issues or malfunctions

DTC P1173 seriousness

DTC P1173 can be considered serious as it may indicate underlying issues with the fuel system that can lead to poor engine performance and increased emissions. If left unaddressed, it can result in further damage to the engine or fuel system components. It is advisable to diagnose and repair the issue promptly to maintain vehicle performance and reliability.

How to diagnose DTC P1173

To diagnose DTC P1173, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1173 code.
2. Inspect the fuel rail pressure sensor and its wiring for any visible damage or corrosion.
3. Check the fuel pressure using a fuel pressure gauge to ensure it is within the manufacturer’s specifications.
4. Test the fuel rail pressure sensor with a multimeter to verify its output voltage against the expected values.
5. Examine the fuel system for any leaks or blockages that could affect pressure.
6. Review the ECM for any software updates or faults that may need addressing.

How to fix DTC P1173 step-by-step instructions

To fix DTC P1173, follow these step-by-step instructions:

1. Clear the DTC using an OBD-II scanner.
2. Inspect and repair any damaged wiring or connectors related to the fuel rail pressure sensor.
3. Replace the fuel rail pressure sensor if it is found to be faulty.
4. Check and replace the fuel filter if it is clogged.
5. Test the fuel pump to ensure it is functioning correctly and providing adequate pressure.
6. Address any vacuum leaks in the intake system that may affect fuel pressure.
7. Re-scan the vehicle to ensure the DTC does not return after repairs.

How to erase DTC P1173

To erase DTC P1173, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Access the scanner’s menu and select the option to clear or erase trouble codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the engine to ensure the code does not reappear.

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