P1191 – OBD-II DTC

OBD-II DTC P1191 – FTS Low – Fuel Pump Temperature Sensor Low

DTC P1191 meaning

DTC P1191 refers to a diagnostic trouble code indicating a low reading from the Fuel Pump Temperature Sensor (FTS). This sensor monitors the temperature of the fuel pump to ensure it operates within safe limits. A low signal from this sensor can suggest that the fuel pump is overheating or that there is a fault in the sensor itself.

DTC P1191 symptoms

Common symptoms associated with DTC P1191 may include:

• Engine performance issues, such as stalling or hesitation
• Difficulty starting the engine
• Increased fuel consumption
• Check Engine Light illuminated
• Unusual noises from the fuel pump

DTC P1191 causes

Several factors can lead to the triggering of DTC P1191, including:

• Faulty Fuel Pump Temperature Sensor
• Wiring issues, such as shorts or open circuits
• Faulty fuel pump
• Overheating of the fuel pump due to lack of fuel
• ECM (Engine Control Module) issues

DTC P1191 seriousness

DTC P1191 can be serious as it may indicate that the fuel pump is not functioning correctly, which can lead to engine performance problems or even engine failure. If left unaddressed, it can result in further damage to the fuel system or other engine components.

How to diagnose DTC P1191

To diagnose DTC P1191, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC P1191.
2. Inspect the Fuel Pump Temperature Sensor and its wiring for any visible damage.
3. Check the fuel pump operation and ensure it is functioning correctly.
4. Test the Fuel Pump Temperature Sensor with a multimeter to verify its readings.
5. Examine the ECM for any faults or updates that may be necessary.

How to fix DTC P1191 step-by-step instructions

To fix DTC P1191, follow these steps:

1. Disconnect the battery to ensure safety while working on the vehicle.
2. Inspect and repair any damaged wiring or connectors related to the Fuel Pump Temperature Sensor.
3. If the sensor is faulty, replace it with a new one.
4. Check the fuel pump for proper operation and replace it if necessary.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Test drive the vehicle to ensure the issue is resolved and the Check Engine Light does not reappear.

How to erase DTC P1191

To erase DTC P1191, 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 DTC menu on the scanner and select the option to erase or clear 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 return.

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