Is the Relay Noise Indicating a Malfunction?

[JasonFitz]

Relay noise occurs when the relay coil has a stable power supply voltage before the vehicle starts and the lights are turned on, ensuring reliable engagement without abnormal sounds. After starting, if the power supply circuit for the relay coil experiences unstable voltage or insufficient power from the source, it can cause unstable relay engagement, resulting in abnormal noise. Battery Discharge: This can be caused by a discharged battery. Use a multimeter to measure the voltage and check if the battery voltage is below 11 volts. Poor Contact: Possible causes include loose motor screws, poor contact at the relay's main terminals, loose or aged screws on the battery leading to increased resistance, or excessively worn motor carbon brushes.