CFL is being used worldwide now. It is energy efficient, compact and have more life than normal incandescent lamp . However, It is costly and have limited warranty. To know about the function and circuitry of CFL, visit In this topic, we will learn how to repair your damaged CFL.   

It is a normal practice around the world to throw the damaged CFL and purchase a new one. But, How many of you have thought that it can be reused with a very negligible amount??? The answer is YES. You want to know how?? Lets know about it.

The damaged CFL can be used in two ways:

1st example :

Lets take example of a 23Watt Philips CFL. Now, all we need is : 1 two feet Tube light, 02 in no wires having length of 1 mtr at least, an insulation tape and Soldering iron

1st step :

Inner PCB of a CFL - an alternate view   Inner PCB of CFL

Remove the old CFL cap and check the inner circuit. You will see four points (solder) for each of the lamp side. Take out the lamp and do the cleaning of circuit using alcohol.


2nd step :

Shoulder the four wires with the terminals. Two at one side and other two at another side. Use insulation tape to cover exposed wires and cover the circuit.

Now, your repaired CFL is ready to use.

Use PCB of damaged CFL to power a Tubelight

2nd example :

Different type of CFLs around usCompact fluorescent lamp normally fails because of damage of some of its parts like transistor, capacitor, diode, resistor or even the transformer. These parts however are low cost and commonly available too.

One of the very common defect in CFL circuit is capacitor failure. If the fuse is burnt, it may damage transistors and resistors also. If the glass tube is damaged, then also you can change it. All types of CFL tubes are available in market. The most common rate is:

  • 2U CFL tube-  20Rs
  • 3U CFL tube – 30Rs
  • Spiral CFL tube -55-65Rs.

1st Step :

Open the cap of CFL. It is the most difficult part of repair. Have patience and use a screw drive to slowly open it as shown in figure.

    How to open a CFL lamp?

2nd Step :

Visually inspect the circuit board. If you observe any deformed/burnt capacitor/diode/resistor, de-solder and remove it out of PCB and carry out the replacement with a newer component of same value or replace it with best possible alternate with a voltage rating of at least or above 250 volts.

Inspect inner PCB components of CFLTest the diodes for its condition. It will conduct if forward biased and will not conduct if reverse biased.

Check the transistors. If you are not able to do it, then go to an electrician and say him to check/replace it.

Closely check the resistors also. If the resistor seems to be burnt, take it out and check its Ohmic reading with a multimeter. It is normally observed that that 30 % of the CFL failure ids caused by open circuit of resistor.

If all of the mentioned components are working fine, then finally check the continuity of tube. Replace it if an open circuit is observed.

3rd step :

Test the circuit by giving main supply in the circuits i/p.

Checking the CFL's PCB by providing power supply

4th Step :

Repack the cap on the Tube. You can seal it by using insulation tape or Feviquick or Plaster of Paris.

Why to wait now. Check your repaired CFL.

If you have learnt anything from it, share this post with your friends and save their money.