P1420 – OBD-II DTC

OBD-II DTC P1420 – Air Pump Circuit Malfunction/ (AIR) System Bank 1

DTC P1420 meaning

DTC P1420 refers to a malfunction in the Air Injection Reaction (AIR) system, specifically indicating an issue with the air pump circuit for Bank 1. The AIR system is designed to reduce emissions by injecting air into the exhaust stream during cold starts, helping to burn off excess hydrocarbons. When the Engine Control Module (ECM) detects a problem with the air pump circuit, it triggers this diagnostic trouble code (DTC). This can occur due to electrical issues, component failures, or circuit malfunctions.

DTC P1420 symptoms

Common symptoms associated with DTC P1420 may include:

• Illuminated check engine light
• Increased emissions during vehicle inspection
• Rough idling or poor engine performance
• Failed emissions test

DTC P1420 causes

Several factors can lead to the triggering of DTC P1420, including:

• Faulty air pump
• Damaged or corroded wiring in the air pump circuit
• Defective relay or fuse related to the air pump
• Malfunctioning air pump control module
• Blocked or restricted air intake to the pump

DTC P1420 seriousness

DTC P1420 is considered a moderate to serious issue. While it may not immediately affect the drivability of the vehicle, it can lead to increased emissions and potential failure during emissions testing. Ignoring this code can result in further damage to the AIR system or related components, leading to more costly repairs.

How to diagnose DTC P1420

To diagnose DTC P1420, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC P1420.
2. Inspect the air pump and its wiring for visible damage or corrosion.
3. Check the air pump relay and fuse for proper operation.
4. Test the air pump for functionality by applying direct power to it.
5. Examine the air intake for blockages or restrictions.
6. Clear the DTC and perform a road test to see if the code returns.

How to fix DTC P1420 step-by-step instructions

To fix DTC P1420, follow these steps:

1. Identify and replace any damaged wiring or connectors in the air pump circuit.
2. Replace the air pump if it is found to be faulty.
3. Replace the air pump relay or fuse if they are defective.
4. Clear any blockages in the air intake system.
5. Recheck the system for proper operation and ensure no DTCs are present.

How to erase DTC P1420

To erase DTC P1420, 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.
4. Select the option to clear or erase the trouble codes.
5. Turn off the ignition and disconnect the scanner.
6. Start the engine and monitor for any reoccurrence of the DTC.

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