P1191 – Land Rover DTC

Land Rover DTC P1191 – Oxygen Sensor Heater Circuit Open Downstream

DTC P1191 meaning on Land Rover

DTC P1191 on a Land Rover indicates an issue with the Oxygen Sensor Heater Circuit Open Downstream. This means that there is an open circuit in the downstream oxygen sensor’s heater circuit, preventing the sensor from reaching its optimal operating temperature.

Land Rover DTC P1191 symptoms

Symptoms of DTC P1191 on a Land Rover may include:

• Check Engine Light illuminated on the dashboard
• Poor fuel economy
• Engine running rough or misfiring
• Reduced engine performance

Land Rover DTC P1191 causes

Common causes of DTC P1191 on a Land Rover include:

• Faulty downstream oxygen sensor
• Open or short circuit in the oxygen sensor heater circuit
• Corrosion or poor connections in the sensor wiring
• Defective Engine Control Module (ECM)

Land Rover DTC P1191 seriousness

DTC P1191 should not be ignored as it can lead to poor engine performance and increased emissions. Driving with this fault may cause damage to the catalytic converter and other engine components over time.

How to diagnose DTC P1191 on Land Rover

To diagnose DTC P1191 on a Land Rover, follow these steps:

1. Use an OBD-II scanner to retrieve the fault code and freeze frame data
2. Inspect the downstream oxygen sensor and its wiring for any visible damage or corrosion
3. Check the resistance of the oxygen sensor heater circuit using a multimeter
4. Inspect the ECM for any signs of damage or malfunction

How to fix DTC P1191 on Land Rover

To fix DTC P1191 on a Land Rover, you can:

1. Replace the downstream oxygen sensor if it is faulty
2. Repair any open or short circuits in the oxygen sensor heater circuit
3. Clean or repair any corroded connections in the sensor wiring
4. If the ECM is faulty, replace or reprogram it as necessary

How to erase DTC P1191 on Land Rover

To erase DTC P1191 on a Land Rover, you can:

1. Use an OBD-II scanner to clear the fault code after the repair has been completed
2. Drive the vehicle for a short distance to ensure the fault does not return

Recommended tools for Land Rover diagnostics

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Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

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