Canon AE-1 meter repair

Hi All,

I'm trying to repair an AE-1 (non-program) with a faulty meter. Upon half-pressing the shutter release the meter bottoms out every time, regardless of camera settings or the amount of available light. After trawling the forums it seems the issue may be with the PX1 IC light sensor behind the prism, perhaps through bad solder connections?

 

I've removed the top cover to inspect, and from what I can see the surface of the sensor looks dirty or possibly corroded (photo attached). And indeed when I shine a bright light directly on to the sensor, I do get some movement in the meter needle through the viewfinder. So I've concluded that the sensor is indeed working, but just not very well, probably due to the surface dirt/corrosion. So my question is, what next? It doesn't look straightforward to replace the sensor, so can I instead compensate for the poor sensitivity via the series of galvanometers above the prism? How would i go about this? Or is there a technique to revive the sensor?

 

I guess it would help if someone could point me in the direction of a service manual for the camera, despite a lengthy search I've been unable to track one down.

 

And finally, this isn't a valuable camera and I'm not looking to buy another. I'm just too stubborn to let it die without a fight.

 

Thanks

 

Sometimes discretion is the greater part of valor. Or something. I like to repair things too, but the printed circuits on these cameras scare me away. So all I can offer is I hope you sort it out.......and buying another working AE-1 is not expensive :]

I DO have the "Program" service manuals. Let me see what i have for the Non-P

In the mean time, whatever you do, do not touch that Tungsten Wire. It runs over those pulleys and connects the ASA to the shutter speeds. Those are a Nightmare if they break, and they are EASY to break.

I can see if i have the AE-1 manual, But it will assume you are already, somewhat, of a camera tech...if you know what i mean. The manuals seem to be more of a How to adjust and measure than any kind of Take-Down or Disassembly instructions. But i am definitey NOT a camera tech.

Do you have a pretty decent DMM.? You are probably going to need one.

I DID read your post, but the AE-1 is not the best camera for a non tech to work on IMHO. For this scenario, i think the Program Model was a better unit.

They are so affordable. Have you thought about just buying the AE-1P.?

the meter bottoms out every time" David S.

Main CPU requires replacement.

Having serviced many of these when they were economical to service, this symptom was indicative of having the large IC chip to the left of the eyepiece blown by a static charge or a flash mounting event redirecting voltage to the non-sync pins...