How check CFL bad or not

You will need to check for power with a test light or multimeter, and confirm a good earth with the same.

Check tbe switch is working correctly and has power to it.

Hi Terry,
The only thing left is cfl tubes. Yes one bad cfl may cause this problem. There is feedback from each cfl and if this feedback is not available, the backlights may not start. Before checking cfls please check all the connectors from inverter to cfls for loose contact and corrosion.
Good luck.

Surely a CFL problem

Have your battety tested for a bad cell, while your driving tbe alternator.is putting out more voltage, more than likely your batt is bad.

I"m guessing you mean, "capacitors"? If capacitors went bad, they likely took other components with them, such as ICs, transistors, etc. Also, getting the values right is pretty important...

Hello
The CFL (cathode florescent lamp) of the LCD has gone bad, it needs replacement, because i faced same problem some time ago and only solution is to replace CFL.
Good Luck

Hi. I have 2 units of T23, 1 unit T22 and T30. All of them has the same problem as yours. 3 units has bad inverter and the other 1 has bad CFL. Inverters can be replaced but if you have bad CFL, it is better to replace LCD screen. If your problem is CFL, you will be able to see a very faint image on your LCD screen. If the LCD is completely black and you can't see anything, then it is an inverter problem.

Inverter is located below the LCD screen. You need to remove the LCD face plate to access the inverter. Please click here for the step-by-step instruction how to access the inverter or replace the LCD screen. Inverter and LCD are available at ebay.

Note: T23 has thin plastic parts that can be easily broken when disassembling.

Good Luck. Let me know further.

2 possible problem, bad LCD or bad CFL. attach an external monitor and start your laptop. if you see a display, you need to bring your laptop to a professional repair center because fixing CFL needs special tool. if you are capable of removing parts of your laptop, you can find LCD assembly on ebay.

You cannot use standard electronic dimmer switches with CFL bulbs, only incandesant bulbs! That is why you are getting the flickering.

With CFL's bulbs installed in a light fixture that has a non-flouresant rated dimmer switch on that circuit, you will cause the standard dimmer to fail.

You have to look at the dimmer package (sometimes printed on the back of the dimmer itself too) to see if it can be used with CFL bulbs,as many are not rated for use with anything other than standard incandesant bulbs.


Hope you found this very helpful and best regards!

Possible that the HV inverter or the CFL tubes are going bad / defective. I suggest to bring the unit to an authorized (BenQ) service center for proper check-up / test & fix the problem. regards