P0122 – OBD-II DTC

OBD-II DTC P0122 – Throttle Position Sensor/Switch A Circuit Low Input

DTC P0122 meaning

DTC P0122 refers to a diagnostic trouble code indicating a low input signal from the Throttle Position Sensor (TPS) or switch A circuit. The TPS is a critical component that monitors the position of the throttle plate in the engine’s intake system. This information is sent to the Engine Control Module (ECM) to adjust fuel delivery and ignition timing accordingly. A low input signal suggests that the TPS is not functioning correctly, which can lead to poor engine performance and increased emissions.

DTC P0122 symptoms

Common symptoms associated with DTC P0122 may include:

• Illuminated check engine light
• Reduced engine power or acceleration
• Unstable or erratic engine idle
• Difficulty in starting the engine
• Increased fuel consumption

DTC P0122 causes

Several factors can lead to the occurrence of DTC P0122, including:

• Faulty throttle position sensor
• Wiring issues such as shorts or open circuits in the TPS circuit
• Corroded or damaged connectors
• Faulty Engine Control Module (ECM)
• Mechanical issues with the throttle body

DTC P0122 seriousness

DTC P0122 is considered a moderate to serious issue. While the vehicle may still be operable, the symptoms can lead to reduced performance and efficiency. Ignoring this code can result in further damage to the engine or related components, as well as increased emissions, which may lead to failing emissions tests.

How to diagnose DTC P0122

To diagnose DTC P0122, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P0122 code.
2. Inspect the throttle position sensor and its wiring for visible damage or corrosion.
3. Check the voltage output of the TPS using a multimeter to ensure it is within the manufacturer’s specifications.
4. Test the TPS connector for proper connection and continuity.
5. Examine the throttle body for any mechanical issues that may affect the TPS operation.
6. Clear the code and perform a road test to see if the code reappears.

How to fix DTC P0122 step-by-step instructions

To fix DTC P0122, follow these steps:

1. Inspect and repair any damaged wiring or connectors related to the TPS.
2. If the TPS is faulty, replace it with a new one.
3. Ensure that the throttle body is clean and free of obstructions.
4. Reconnect all connectors securely and ensure proper grounding.
5. Clear the DTC using an OBD-II scanner.
6. Test drive the vehicle to confirm that the issue is resolved and the code does not return.

How to erase DTC P0122

To erase DTC P0122, 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 check engine light is off.

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