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Powerbook 2400c inverter

jlindsay26

Well-known member
Working on a powerbook 2400c I thought it had a bad backlight so I replace the bulb but still no backlight bought a tester for the bulb and confirm it's working so I supect it's the inverter board so I figured I ask a few questions. in the attach picture does anyone know if F1 is a fuse? It look like it marked 1.25A ? 73 I checked and it doesn't have continuity. Second question second picture on transformer should I have conitunity between the two right soldered connection. lastly open to any suggestion on things to check/testing. Thanks in advance.
 

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macuserman

Well-known member
Following in case you figure this out, I've got several of these that could use repair. Seems to be a failure-prone part.
 

jlindsay26

Well-known member
I think your right since I have two and both aren't working. I'm almost wondering if I could wire-in a replacement inverter or I guess I could permanently attach the tester to the powerbook.
 

MacUp72

Well-known member
I think to narrow problems down quicker one should have one working machine and swap part for part.
its enerving..like the 3400s
 

Garrett B

Well-known member
Working on a powerbook 2400c I thought it had a bad backlight so I replace the bulb but still no backlight bought a tester for the bulb and confirm it's working so I supect it's the inverter board so I figured I ask a few questions. in the attach picture does anyone know if F1 is a fuse? It look like it marked 1.25A ? 73 I checked and it doesn't have continuity. Second question second picture on transformer should I have conitunity between the two right soldered connection. lastly open to any suggestion on things to check/testing. Thanks in advance.
Where did you find a replacement bulb? Trying to track down similar issues on mine.
 

macuserman

Well-known member
Where did you find a replacement bulb? Trying to track down similar issues on mine.
Parts for these are pretty much unobtanium, you have to just grab them when they come up which is rarely, I have a pretty large stash of parts for these machines I'll be liquidating at some point when I have time to go through and build out the best units.
 

jlindsay26

Well-known member
I’ll mention replacing the bulb isn’t too difficult but I would suggest getting a tester if your not positive the bulb is bad
 

Garrett B

Well-known member
I’ll mention replacing the bulb isn’t too difficult but I would suggest getting a tester if your not positive the bulb is bad
Thank you for the info - super helpful. I did verify the bulb on mine is bad. Has a really pronounced red tint to it, indicating it's on its way out.

I take it the controller board has to be moved out of place to access the bulb? Trying to avoid messing with this panel as much as I can due to how rare they seem to be.

LCD (2).jpg
 

jlindsay26

Well-known member
Thank you for the info - super helpful. I did verify the bulb on mine is bad. Has a really pronounced red tint to it, indicating it's on its way out.

I take it the controller board has to be moved out of place to access the bulb? Trying to avoid messing with this panel as much as I can due to how rare they seem to be.

View attachment 59581
I'll take a few picture and post them later today I bought bulbs from this seller tvrepairledtester listed as follows I have extras if you want a couple send me a PM I'll be happy to send you two if you cover the shipping.

220mm*2mm CCFL Backlight Lamps for 10.4'' Laptop LCD Monitor Brand New​

 

jlindsay26

Well-known member
Here are some pictures of removing the backlight remove the three circled screws this should allow you to remove the metal frame around the front of the screen
 

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jlindsay26

Well-known member
next remove these screws and you can pull back the controller board there's and edge connector under the arrow so you'll need to pry that loose
 

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jlindsay26

Well-known member
peel the controller board back pull the back light out remove the light and solder new bulb in
 

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Powerbook27364

Well-known member
I just got a 2400c/240 and it’s display is smashed. The backlight doesn’t turn on through and brightness controls don’t change it either. I was wondering could this be a bad inverter or backlight? Is there any way to know which without a bulb tester?
 

jlindsay26

Well-known member
I just got a 2400c/240 and its display is smashed. The backlight doesn’t turn on through and brightness controls don’t change it either. I was wondering could this be a bad inverter or backlight? Is there any way to know which without a bulb tester?
Not PowerBook specific but I seen videos where people hook up backlights to a working laptop’s inverter to test. The tester I got was pretty cheap on Amazon currently $10 but you need to use you own 12volt power supply.
 

Powerbook27364

Well-known member
I don’t think I have any other inverters that would work. Voltage is 0v going to the backlight. I need to try to get a display and inverter now it seems which is going to be difficult.
 

jlindsay26

Well-known member
I don’t think I have any other inverters that would work. Voltage is 0v going to the backlight. I need to try to get a display and inverter now it seems which is going to be difficult.
It does it seems like this is a point of failure for this model and finding parts is difficult. I’m in the same boat.
 

Powerbook27364

Well-known member
Would there be any way to use a new inverter or wire direct power to the backlight? I’m not sure what else the inverter does but I Might just do that if it only powers the backlight
 

jlindsay26

Well-known member
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