Hi, I am new to this site. I have a Halfords 2 or 4 amp, switched mode car battery charger made, about 10 years old. It was working fine, until I went to use it last week. When plugged in there are no LEDs on, and no voltage on the output, a good 12v car battery has to be connected for the charger to work. I have opened the plastic case and done many checks for any component burn marks or short circuits. The circuit uses a Fairchild FAN7554 PWM controller, with a Fairchild FQPF10NC60C N channel Mosfet as the switching device. I have a Fairchild FAN7554 general application sheet. The FQPF10NC60C device was not shorted, after replacing with new device, no change. I am able to read the DC supply voltage of 330v DC, on the 100uf storage capacitor. I believe the FAN7554 is not working because it does not seem to have a starting or running voltage. If needed I will replace it, but would like to find out it is faulty first. Any help would be gratefully received.
