Common failure is broken capacitor C3. It is possible mainly at cheap lamps, where are used cheaper components for lower voltage. Whet the pipe doesn't lights up on time, there are risk of destroying transistors Q1 and Q2 and next resistors R1, R2, R3 and R5. When lamp starts, changer is very overloaded and transistors usually doesn't survive longer temperature overloading. When the pipe serve out, electronics is usually destroyed too.
Repair of electronics
Repair of electronics usually means change of capacitor C3 if he is brobek. When burns fuse, probably will be damaged transistors Q1, Q2 and resistors R1, R2, R3, R5. You can replace fuse with resistor 0R5. Failures can be multiplied. For example, when is shorted capacitor there can be thermally overloaded transistors and will be destroyed. Best transistors for replacing of original types are MJE13003, but it is not easy to find them. I replaced them with BD129, but they are not available now. There exists other variants like a 2SC2611, 2SC2482, BD128, BD127, but I am not sure if they will be long-life. Original transistors are not available on our market. If doesn't matter size of case TO220, it's possible to use transistors MJE13007.
Lamp is usually compounded of two parts. One is plastic cover with holes for pipe and bills. Tube is agglutinated to it.
Most of these compact fluorescent lamps use same or very similar wiring. more expensive lamps use a little complicated wiring with electrode preheating and thanks to it they have longer lifetime. Repairing of these lamps not pay off, because price of cheaper types are very low now and price of human work is much higher. Wiring diagrams originates while repairing of lamps and they are only for study or repair uses. Informations are from retracing of lamps and from sources in a link section.
Schematics and photos
Compact fluorescent lamp Bigluz 20W use classic wiring with a small changes. Values of parts are modified for bigger power.
Photo of opened lamp Bigluz 20W.
Lamp Isotronic 11W use a little modified wiring, where doesn't exists starting circuit with a diac. Lamp starts probably thanks to capacitor C1.
Lamp Luxtek 8W use classic wiring with a small changes. Interesting is only thermistor, which probably makes light start and filament preheating.
Photo of board with a electronics and upper side of cover.
Lamp Maway 11W use different wiring too like Isotronic lamp.
Lamp Maxilux 15W use classic wiring.
Lamp Polaris 11W has a small thread and changes some values of components. Wiring is classic.
BrownieX 20W lamp has a simplified wiring like a Isotronic lamp.
PHILIPS ECOTONE 11W
Lamp PHILIPS ECOTONE 11W use again simplified wiring like a Isotronic lamp.
Photography of opened Philips lamp.
Lamp IKEA 7W has classic wiring like a Lixar 11W.
Photography of opened lamp IKEA 7W
OSRAM DULUX EL 11W
Lamp OSRAM DULUX EL 11W has again classic wiring with only few changes. She has a small thread and was a fully functional.
OSRAM DULUX EL 21W
Lamp OSRAM DULUX EL 21W has a classic wiring diagram. In contrast to a previous OSRAM lamp doesn't have thermistor for slow start. She has overburned one filament.
EUROLITE 23W (October 13 2008)
Lamp EUROLITE 23W has a classic wiring diagram. For schematics thanks to Mard.
SINECAN 5 2x 26-30W (October 13 2008)
Electronic ballast SINECAN 5 for two fluorescent tubes has identical circuit like most of compact fluorescent lamps. Little differency is in powering tubes before D6 diode and wiring of start capacitors C10 a C11 about tubes. I don't understand exactly why this is wired this way. Ballast doesn't have fuse, but only thin wire. Ballasts was broken due to blowed electrolytic capacitors. It breaks transistors and resistors R3, R4, R5 and R6.
Photography of open ballast.
Inside a huge PCB factory: https://www.youtube.com/watch?v=_XCznQFV-Mw