Projector warning encountered while disassembling


2016-02-06 7:47 am
I'm disassembling a Canon SX60 projector for lab use. I have already extracted all the optical and electronic parts out of the case and removed the lamp.

If I left the ignition signal wire connecting from mainboard to power supply, I can hear "Di Di Di" several times, which the system trying to ignite the lamp. A few attempts later, the projector throws lamp failure warning by blinking the power light twice at a time.

By connecting one pin to ground, I bypassed the lamp detection. It works. Then I bypassed all the fans by connecting the fan tach sensor pins to the ground. It works.

Then the weirdest thing is when I separated the lens from the LCD part, separate the lens zooming motors and controller from the lens scope, and disconnect the lens zooming motors and its controller from the mainboard, the projector throws temperature abnormal warning by blinking once at a time.

So I reconnect those two components to the mainboard. Then when I start it again, the motors keep rotating, and by illuminating the lcd, I can see there seems to be a warning in a white box flashing by, then the start screen shows again and again(means the projector starts over and over). And finally it throws a lamp failure warning flashing. It takes longer to finally give the warning.

What I don't understand is why it's a lamp failure. Is there any sensor that can check if there is light coming out of the scope? Or could it be I connected the wrong pin to bypass the lamp check? There are six pins in that cable. The pin I connected to ground was measured 3.3V before.

Sorry for my poor english. I know it's verbose, but please help. Thanks!