[4.20.16] GH1 Shutter Repair
your Panasonic GH1 Boot up, get sad and display the "PLEASE TURN CAMERA
OFF AND THEN ON AGAIN" message? Have you not been able to get out of
this infinite loop?
Follow along on the adventure of un-sticking and exercising your
shutter motor, bring the beast back to life.
whats going on?
message can appear for a number of reasons, its the catch-all
'somethings up, maybe a power cycle will fix it' There are a few forum posts
with this error and they all end at the same point, remove the battery
and hope for the best or return the camera. In my instance I could hear
the shutter motor start up and halt then the camera displays the error
message. I've run around with this thing a bunch, its more than likely
its absorbed its fair share of grime and beatings, but on to figuring
out whats going on.
i thought, hey could just be the internal bios battery died or
something simple. This thing has more parts than a swiss watch, so I
went for the double-sided tape sorting method. This has worked really
well in the past for holding itty bitty screws in place, adding a
'really bad artists rendition' of where the screw came from on a post
it also helps to keep track of things. Strips of double sided
are laid on the bench top to keep hold of the screws, as this prevents
sneezes or well intentioned compressed air blasts from scooting parts
all over the place.
|Finding the shutter assembly
So I tore the whole camera apart. There's a repair manual [link]
which is useful for figuring out how the thing comes apart / goes back
together. Realistically it takes a while and there's a bit of a 'whats
holding this in place' dance. The shutter assembly itself is powered by
a tiny DC motor, a reduction gearbox and a cam-spring assembly for
winding up and firing the shutter. This allows the motor to spool
relatively open loop for shutter actuations. A hall effect position
sensor is used to determine where the rotor is.
sketchily re-inserted the battery into the camera, with the pile of
ribbon connectors connected and found that the shutter motor attempted
to move, stalled and then stopped. The camera error is most likely a
'hey the hall effect position sensor hasnt seen movement, somethings
up' timeout error. I disconnected the ribbon cable feeding the motor
and soldered 2 wires to the dc motor to see if the motor itself was
had no idea what voltage the motor was, but given that the camera
battery is 7v, it was probably somewhere between 3 and 6ish volts to
fire over the motor. I used a current limited supply, set to 3v 100mA
and tested the motor. After a few jitters, it sprung back to life
<video below>. It appears the little reduction gearbox
had dried up and turned sticky, I added some silicone lubricant and
spooled the shutter a few times.
|Cycling a GH1 Shutter, External Power supply
lo the GH1 shutter cycled from an external supply to wake it back up /
cycle the new lubricant back into the small shutter gearbox. Again,
this is powered by an external CURRENT LIMITED power supply set at 3v
0.1A. The current limit is an important caveat to this, as it prevents
supplying very high current to a tiny motor, possibly causing damage.
|Putting everything back together
|Remove the soldered in place wires to the shutter motor and use the service manual [link] to help re-assemble the beast. You labeled your screws and used the doublesided tape + post-it note method didnt you?
|AND NOW YOUR CAMERA WORKS AGAIN, HOPEFULLY.
- This may very well destroy parts of your camera, remember to
disconnect the ribbon cable that normally drives the dc motor on the
shutter before applying external power
have questions or comments, ask below or send over an email.
careful, im not responsible for your camera jumping off the table while excercising its shutter)
Rensselaer Polytechnic Institute
Electrical & Electrical Power