B1478 – Power Window One Touch Up/Down Activated Simultaneously
The ODBII code B1478 indicates a malfunction related to the power window system, specifically that the one-touch up/down feature for the power windows has been activated simultaneously, which is not a normal operation.
The severity of ODBII code B1478 is moderate.
Common Causes For: B1477 Wiper Hi/Low Circuit Motor Short To Ground
- Faulty power window switch
- Shorted wiring or connectors
- Malfunctioning window motor
- Defective body control module (BCM)
- Poor ground connection
- Corroded or damaged wiring
- Incorrectly programmed BCM
- Faulty window regulator
Common misdiagnosis for B1478 Power Window One Touch Up/Down Activated Simultaneously
- Faulty window switch
- Defective power window motor
- Wiring issues or shorts
- Body control module (BCM) failure
- Faulty door module
- Incorrectly programmed or calibrated system
- Battery or charging system problems
- Ground connection issues
Common Troubleshooting Steps
When dealing with OBD-II code B1478, which indicates an issue with the power window one-touch up/down feature being activated simultaneously, there are several common troubleshooting steps you can follow to diagnose and potentially resolve the issue. Here’s a structured approach:
- Check for Additional Codes: Use an OBD-II scanner to check for any other related trouble codes. Sometimes, multiple codes can provide more context for the issue.
- Inspect the Power Window Switch: **Visual Inspection: Check the power window switch for any signs of damage, wear, or corrosion.
- **Functionality Test: Test the switch to ensure it operates correctly. If the switch is faulty, it may need to be replaced.
- Examine Wiring and Connectors: **Wiring Inspection: Look for damaged, frayed, or shorted wires in the power window circuit.
- **Connector Check: Ensure that all connectors related to the power window system are secure and free of corrosion.
- Test the Power Window Motor: **Motor Functionality: Test the power window motor to ensure it is functioning properly. If the motor is faulty, it may need to be replaced.
- **Voltage Check: Use a multimeter to check if the motor is receiving the correct voltage when the switch is activated.
- Check the Window Regulator: Inspect the window regulator for any mechanical issues that could prevent the window from operating correctly. If the regulator is damaged, it may need to be replaced.
- Inspect the Body Control Module (BCM): The BCM controls various electrical functions in the vehicle, including the power windows. Check for any faults in the BCM that could be causing the issue.
- If necessary, reprogram or replace the BCM.
- Look for Ground Issues: Ensure that all ground connections related to the power window system are secure and free of corrosion. Poor grounding can lead to erratic behavior.
- Check for Water Intrusion: Inspect the door and window seals for any signs of water intrusion that could affect electrical components.
- Reset the System: Sometimes, resetting the vehicle’s computer can clear temporary faults. Disconnect the battery for a few minutes, then reconnect it and see if the code reappears.
- Consult the Service Manual: Refer to the vehicle’s service manual for specific troubleshooting steps and wiring diagrams related to the power window system.1
- Professional Diagnosis: If the issue persists after performing the above steps, consider seeking help from a professional mechanic or an automotive technician who can perform more advanced diagnostics. By following these steps, you should be able to identify the root cause of the B1478 code and take appropriate action to resolve the issue.