Troubleshooting of Solar Street Lights

6 steps to do troubleshooting of solar street light

Solar-powered street lights are trending these days. Not only they are cost-efficient but also help you in doing your part in saving and conserving Mother Nature. But did you know you can fix it with simple tricks?

It is very frustrating to find out that your new solar street lights are not working, it could cause you a lot of inconveniences. The good thing is, these issues can be solved even if you are not a tech-savvy person. We will take you through some tips and tricks that may come in handy if your new solar street lamps are not working.

Why won’t my solar street lights come on?

Most of the time, solar lights do not function due to faulty batteries. If the lights work with the regular batteries, then you can go on to establish whether the problem is caused due to the rechargeable batteries of the solar lights or due to the solar panel. But we do not rule out that it is caused by the failure of the solar controller.

1. Observe the situation of indicator on the sensor

  1. The Greenlight is always on (battery voltage is higher than 12V)-function is normal
  2. Fast blinking green light (charging once every 1 second)-function is normal, charging
  3. Slow blinking green light (1 time in 3 seconds indicates that the battery is fully charged)-function is normal and fully charged
  4. Traffic lights light up together (battery voltage is lower than 12V)-function is normal
  5. The red light is always on (the battery is over-discharged) — the battery function is abnormal and the battery is depleted
  6. Red light flashes slowly (once every 1 second, the load is disconnected, and the light is off)-LED function is abnormal, and the light source cable is not connected well
  7. Fast red flashing (2 times per second, indicating that the load is short-circuited and the light is not on)-LED function is abnormal, the positive and negative poles of the light source are reversed
  8. No instructions (the battery is dead or the cables are not in contact or the controller is broken)



2. Troubleshooting methods for solar street lights

A. No lighting at night, but there are indicators

1. The green light flashes.

First check whether there is strong light around, or whether the moonlight is very bright. If there are two cases, remove the strong light or remove the solar street light; if there is no strong light around, you need to replace the controller.

2. The red light is flashing and the load is not on.

1) Check the controller function. Call the normal function controller from the side to the light body, and connect to test whether the load is working normally. If it is normal, it means that there is a problem with the controller, just replace the controller; if the load is still off, the LED light source is defective.
2) Check the function of the LED light source. Use adjustable power supply to adjust the light source voltage to 36V / 24V / 12V (according to your light source voltage), test whether the LED light source is on normally, if it is not confirmed, replace with a new light source

3. The red light is always on and the battery is no power.

1) Observe whether there is no sun for several days in a row, wait for the next day to charge the battery, and observe the charging status of the lamp during the day. If the green light flashes during the day, it indicates that the charging is normal. The lamp will be lighting automatically at night
2) If you charge the battery on sunny days for a few days, and the light still does not turn on at night, the solar panel cannot be charged or the battery cannot be discharged.
a. Test Solar Panel Function (please refer to B below)
b. Test battery function (please refer to B below)
c. Precautions:
1) Record the battery voltage value in the morning and the battery voltage value in the evening. If the voltages in the evening and morning are consistent, the battery cannot be charged.
2) When measuring the voltage of the solar panel with a multimeter, you must place the solar panel under the sun, open the junction box to test the charging voltage, or directly test the voltage of the waterproof cable connector
3) Testing the solar panel Voltage, current; Testing the battery Voltage, current.

Solar lights doesn't working

B. No lighting at night, no indicator light on microwave sensor

1. Check the waterproof connector. Unplug the solar panel-to-plug, and check whether the waterproof-to-plug is shorted by water
2. Test the function of the solar panel. Unplug the solar panel plug, open the solar panel junction box, and place it in the sun. Use a multimeter to measure the voltage of the solar panel. If the voltage of the solar panel is higher than 16V or 32V, the solar panel is normal.


3. Test the battery function. Unplug the battery cable and measure the battery voltage with a multimeter. If it is 0v, the battery is in deep protection due to long-term power loss. Use a DC power supply and adjust the voltage to 14.6 or 29.2 (lithium iron phosphate), 12.6V 25.2V (ternary lithium ), Charge and activate the battery. If the voltage is lower than 10V or 20V (lithium iron phosphate), 8v or 16V (ternary lithium), the battery is faulty, replace the battery. If the battery voltage is higher than 12.6 or 25.2 (lithium iron phosphate), 10.8 or 21.6 (ternary lithium), the battery is normal, replace the controller.


C. Short lighting time at night

1. Check whether there are trees, fences, electric wires or light poles above or beside the solar street light that affect the sunlight. If so, remove the blind or solar street light.
2. Check whether the installation angle of the solar panel is perpendicular to the noon sun. If not, adjust the installation angle of the solar panel.
3. Check whether the solar panels are covered by leaves, bird feces or sand and other obstructions. If so, clean them up.

3. Why do solar street lights need to set battery protection voltage?

The flashing red light indicates a loss of power. If the light has been charging for more than 4-7 days in sunny weather, it means that the battery cannot be charged and the battery may be protected.
Once the battery is overcharged or over-discharged, it will be protected, it will not be charged, and the light will not turn on again. At this time, we need to charge the battery for a few days to release the battery protection. Then the solar lamp can be working again.

Solar street lights are generally set with factory protection voltage. If we do not set the protection voltage, the battery will be vented, which will damage the battery.

4. Why does the battery run out?

1. This solar street lamp has a large amount of discharge but a small amount of charge every day. If the battery is in a state of discharge> charge for a long time, the battery will lose power

2. See if the solar panel is blocked by the obstruction? Solar panels are exposed to the sun every day, is it enough (4-6 hours)? Is the solar panel oriented correctly (facing the sun)?

3. If the power output of the led light is too big, the battery may run out of power.

5. How to activate a protected battery

1. Use an external power supply to charge the battery directly. Please adjust the voltage to 14.6V or 29.2 V(lithium iron phosphate), 12.6V or 25.2V (ternary lithium ), Charge and activate the battery. When the battery voltage rises from 0V to 9V, the battery is activated. You can continue to use the external power supply to fully charge the battery, or you can connect the solar panel and controller to charge the battery.


2. If you do not have an external power supply, you can directly charge the battery with a solar panel (need to cut the solar panel and the battery and then connect them together). After 10 minutes, measure the battery voltage. If the battery voltage rises to 9V, the battery is activated Already. (We do not recommend charging the battery directly with solar panels, unstable current may damage the battery)

6. Normal working condition

Led lighting working, the green light on the microwave sensor is flashing


1 thought on “Troubleshooting of Solar Street Lights”

  1. If I have the green light on my solar powered street light is that on the green light stays on but doesn’t light up at nights

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