B1420 – OBD-II DTC

OBD-II DTC B1420 – Passenger Power Window Motor Circuit Short To Battery

DTC B1420 meaning

DTC B1420 refers to a diagnostic trouble code indicating a short circuit in the passenger power window motor circuit to battery. This code is generated when the vehicle’s onboard diagnostic system detects an abnormal voltage condition in the power window motor circuit, suggesting that the circuit is directly connected to the battery, which can lead to potential electrical issues.

DTC B1420 symptoms

Common symptoms associated with DTC B1420 may include:

• Passenger power window not functioning
• Power window motor making unusual noises
• Window may be stuck in the up or down position
• Other electrical components in the vehicle may exhibit erratic behavior

DTC B1420 causes

The causes of DTC B1420 can include:

• Short circuit in the wiring harness
• Faulty power window motor
• Damaged or corroded connectors
• Issues with the power window switch
• Faulty body control module (BCM)

DTC B1420 seriousness

DTC B1420 is considered a moderate to serious issue. While it may not affect the vehicle’s drivability, it can lead to further electrical problems if not addressed. Additionally, a malfunctioning power window can pose safety risks, especially if the window is stuck in an open position.

How to diagnose DTC B1420

To diagnose DTC B1420, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the DTC.
2. Inspect the wiring and connectors related to the passenger power window motor for any visible damage or corrosion.
3. Test the power window motor for proper operation using a multimeter.
4. Check the power window switch for functionality.
5. Examine the body control module for any faults or issues.

How to fix DTC B1420 step-by-step instructions

To fix DTC B1420, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety.
2. Inspect and repair any damaged wiring or connectors in the power window circuit.
3. Replace the power window motor if it is found to be faulty.
4. Test the power window switch and replace it if necessary.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Test the power window operation to ensure the issue is resolved.

How to erase DTC B1420

To erase DTC B1420, 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. Confirm the action and wait for the scanner to complete the process.
6. Disconnect the scanner and start the vehicle to ensure the code does not reappear.

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