Re: iMac a1225 Power Supply Board LITEON PA-3241-02A1 Repair



I read through the other threads for this power supply, but I seem to have a different problem than them. For instance, there is no trickle power in my case. This leads me to think that there is another different problem that has not been addressed by that thread.

That being said, while poking around while the board was live I was distracted by something and blew up one of the power transistors. I might just cut my losses and buy a new board. Or better yet, just get rid of the iMac since...

Re: iMac a1225 Power Supply Board LITEON PA-3241-02A1 Repair

I replaced the capacitors in question, and there is still no output or trickle voltage. Any help figuring out the next step in troubleshooting? Thanks.

I did some basic tracing of AC input voltage up until the rectifier (A GBU808 Bridge Rectifier). The output there is 160V DC as measured by my scope. Is that a standard output that should be expected?

Hi! This will be my first post on these forums, but after browsing for a long time I trust you guys the most to help me out with switchmode power supply issues.

For a preface, I just came into possetion of two 2009 iMacs, a 20" a1224 and the 24" a1225 that I am currently working on. (The a1224 has a problem with either the inverter or the screen, but there's an inverter on the way - so we shall see!)

The 24" iMac I am working on has a problem with the power supply. For those that don't know, iMac's have four diagnostic LED's that are used to diagnose...

Re: New Members - please post your introductions here

Hi guys! Amateur electronics technician based in Missouri. Still learning things all the time, but I'm fairly expereinced working on HV equipment since I have primarily been working on oscilloscopes and other HV radio equipment like amplifiers.

Great to be here!