Problem:The light bar flickers just after installation; or only the first half lights up while the second half is dim; or the entire light bar does not light up at all.
Root Causes:
Power supply power rating is falsely advertised: The rated power of the power supply is less than the total power of the light bars.
Significant voltage drop: The light bars are connected in a series that is too long, or the power cord is too thin, resulting in insufficient voltage at the far end.
Incorrect voltage connection: For example, connecting a 12V light bar to a 24V power supply (which will burn out the light bar) or reversing the positive and negative terminals.
Solutions:
Power Supply Configuration (Leave a Margin):
The rated power of the power supply must be ≥ total power of the light bars × 1.2 (reserve a 20% margin).
Solving “Bright Front, Dim Back” (Add Circuits):
Do not connect all the light bars end-to-end in a single long series.
Run a return wire from the power supply for every 8–10 light bars. That is, use a parallel connection method to ensure that each light bar receives the same voltage.
Wiring Inspection:
Before installation, use a multimeter to measure the output terminal. Confirm that the positive and negative terminals are correctly connected and that the voltage level matches before powering on.