I have a working T3i and can speak to some of that.
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I have a working T3i, set to movie mode (the only one I use)
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With Magic Lantern (which isn't really "installed", it's just added to the SD): The red led flashes any time you either open or close either the battery door or the SD door.
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Without Magic Lantern (Canon v1.0.2) and a good SD card: The red LED flashes only when you turn it on (twice, quickly), or when you open the battery compartment (once) (not when you close it? I thought I'd seen that.)
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Without Magic Lantern (Canon v1.0.2): The red LED flashes ONLY when you turn it on, with a good SD inside OR when you open the battery compartment (not when you close it?)
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With Magic Lantern (which isn't really "installed", it's just added to the SD): The red led flashes any time you either open or close either the battery door (long flash, possibly 2 or more) or the SD door (similar.) When you turn the camera on, there are many flashes over several seconds and one long flash when you turn it off.
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If there is no SD card in the camera, it appears dead -- opening and closing doors and inserting the battery does nothing. Without an SD, there is no LED flash, but the mirror clicks and the LCD turns on, saying "No card in camera".
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With no SD card in the camera, the LED never blinks when opening and closing either door. However, when you turn the camera on, the mirror clicks and the LCD turns on, saying "No card in camera".
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NOTE!! If you insert a dead SD card (e.g., an empty microSD adaptor), the LED will NOT blink, there's no mirror click and the LCD will not turn on. Removing that and inserting a good SD card WON'T FIX IT -- the camera still appears to be dead. If you remove and re-insert the battery (quickly, so you don't lose your configuration), the camera works normally. There is indeed an SD door switch (as Tony said), but the camera evidently reads the SD before the LED flash. So, if your camera appears to be dead, try a new/better SD card.
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With a dead SD card (e.g., an empty microSD adaptor), the LED doesn't blink, there's no mirror click and the LCD will not turn on -- the camera appears to be dead. Inserting a good SD card WON'T FIX IT -- the camera still appears to be dead. If you remove and re-insert the battery (quickly, so you don't lose your configuration), the camera then works normally. I conclude therefore that the camera reads the SD before flashing the LED. So, if your camera appears to be dead, try a new/better SD card and remove and reinsert the battery.
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Irisheyes and Dana ask where the switches are. You can't get to the connections of either door switch without opening the camera; Tony was talking about the little rectangular pins on each door that push the switches. If a pin breaks off, that could cause apparent death. The battery-compartment-door pin is right below the arrow printed on the inside of the door -- opposite the hinge, toward the center of the camera. The SD-card-door pin is opposite the hinge, toward the bottom of the camera. The SD-door pin is about 0.1" x 0.05"; the battery-door pin is slightly larger. It's easier to see the switches when you know what's pushing them.
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Irisheyes and Dana ask where the switches are. You can't get to the electrical connections of either door switch without opening the camera; but you can see the switch buttons. It's easier to find the switches when you know what's pushing them. Tony was talking about the little rectangular pins on each door that push the switches. If a pin breaks off, that could cause apparent death. The battery-compartment-door pin is right below the arrow printed on the inside of the door -- opposite the hinge, toward the center of the camera. The SD-card-door pin is opposite the hinge, toward the bottom of the camera. The SD-door pin is about 0.1" x 0.05"; the battery-door pin is slightly larger.
I have a working T3i and can speak to some of that.
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With Magic Lantern (which isn't really "installed", it's just added to the SD):
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With Magic Lantern (which isn't really "installed", it's just added to the SD): The red led flashes any time you either open or close either the battery door or the SD door.
-
If there is no SD card in the camera,it appears dead -- opening and closing doors and inserting the battery does nothing.With a flash card installed, any time you either open or close either the battery door or the SD door, the red led will flash.
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Without Magic Lantern (Canon v1.0.2): The red LED flashes ONLY when you turn it on, with a good SD inside OR when you open the battery compartment (not when you close it?)
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Without Magic Lantern (Canonv1.0.2)
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If there is no SD card in the camera, it appears dead -- opening and closing doors and inserting the battery does nothing. Without an SD, there is no LED flash, but the mirror clicks and the LCD turns on, saying "No card in camera".
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The red LED flashes ONLY when you turn it on, with an SD inside OR when you open the battery compartment. Without an SD, there is no LED flash, but the mirror clicks and the LCD turns on, saying "No card in camera".
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NOTE!! If you insert a dead SD card (e.g., an empty microSD adaptor), the LED will NOT blink, there's no mirror click and the LCD will not turn on. Removing that and inserting a good SD card WON'T FIX IT -- the camera still appears to be dead. If you remove and re-insert the battery (quickly, so you don't lose your configuration), the camera works normally. There is indeed an SD door switch (as Tony said), but the camera evidently reads the SD before the LED flash. So, if your camera appears to be dead, try a new/better SD card.
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NOTE!! If you insert a dead SD card (e.g., an empty microSD adaptor), the LED will NOT blink, there's no mirror click and the LCD will not turn on. Removing that and inserting a good SD card WON'T FIX IT -- the camera still appears to be dead. If you then remove and re-insert the battery (and if you're quick enough you won't lose your configuration), the camera works normally -- flashes when either door is opened or closed (with ML). There is indeed an SD door switch (as Tony said), but the camera evidently reads the SD before the LED flash. So, if your camera appears to be dead, try a new/better SD card.
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Irisheyes and Dana ask where the switches are. You can't get to the connections of either door switch without opening the camera; Tony was talking about the little rectangularpins on each door that push the switches. If a pin breaks off, that could cause apparent death. The battery-compartment-door pin is right below the arrow printed on the inside of the door -- opposite the hinge, toward the center of the camera. The SD-card-door pin is opposite the hinge, toward the bottom of the camera. The SD-door pin is about 0.1" x 0.05"; the battery-door pin is slightly larger. It's easier to see the switches when you know what's pushing them.
+
Irisheyes and Dana ask where the switches are. You can't get to the connections of either door switch without opening the camera; Tony was talking about the little rectangular pins on each door that push the switches. If a pin breaks off, that could cause apparent death. The battery-compartment-door pin is right below the arrow printed on the inside of the door -- opposite the hinge, toward the center of the camera. The SD-card-door pin is opposite the hinge, toward the bottom of the camera. The SD-door pin is about 0.1" x 0.05"; the battery-door pin is slightly larger. It's easier to see the switches when you know what's pushing them.
I can answer some of that. First, if there is no SD card in the camera, it will appear dead -- opening and closing doors and inserting the battery does nothing. If there's a flash card installed, any time you either open or close either the battery door or the SD door, the red led will flash. You can't get to the connections of either door switch without opening the camera but you can see the little pins (detents?) on each door that push the switches. If a detent breaks off, that could cause apparent death.
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I have a working T3i and can answer some of that.
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NOTE!! (I have a working T3i and tried and verified this.) If you insert a dead SD card (I used an microSD adaptor with no card), the LED will NOT blink and removing that and inserting a good SD card WON'T FIX IT -- the camera appears to be dead. If you then remove and re-insert the battery (and if you're quick enough you won't lose your configuration), the camera works normally -- flashes when either door is opened or closed. There is indeed an SD door switch (as Tony said), but the camera evidently reads the SD before flashing the light. So, if your camera appears to be dead, try a new/better SD card.
+
With Magic Lantern (which isn't really "installed", it's just added to the SD):
-
Irisheyes and Dana ask where the switches are. Tony was talking about the pins on the doors that push the switches. The battery-compartment-door pin is right below the arrow printed on the inside of the door -- opposite the hinge, toward the center of the camera. The SD-card-door pin is opposite the hinge, toward the bottom of the camera. The SD-door pin is about 0.1" x 0.05"; the battery-door pin is slightly larger. It's easier to see the switches when you know what's pushing them.
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If there is no SD card in the camera, it appears dead -- opening and closing doors and inserting the battery does nothing. With a flash card installed, any time you either open or close either the battery door or the SD door, the red led will flash.
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Without Magic Lantern (Canon v1.0.2)
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The red LED flashes ONLY when you turn it on, with an SD inside OR when you open the battery compartment. Without an SD, there is no LED flash, but the mirror clicks and the LCD turns on, saying "No card in camera".
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NOTE!! If you insert a dead SD card (e.g., an empty microSD adaptor), the LED will NOT blink, there's no mirror click and the LCD will not turn on. Removing that and inserting a good SD card WON'T FIX IT -- the camera still appears to be dead. If you then remove and re-insert the battery (and if you're quick enough you won't lose your configuration), the camera works normally -- flashes when either door is opened or closed (with ML). There is indeed an SD door switch (as Tony said), but the camera evidently reads the SD before the LED flash. So, if your camera appears to be dead, try a new/better SD card.
+
+
Irisheyes and Dana ask where the switches are. You can't get to the connections of either door switch without opening the camera; Tony was talking about the little rectangularpins on each door that push the switches. If a pin breaks off, that could cause apparent death. The battery-compartment-door pin is right below the arrow printed on the inside of the door -- opposite the hinge, toward the center of the camera. The SD-card-door pin is opposite the hinge, toward the bottom of the camera. The SD-door pin is about 0.1" x 0.05"; the battery-door pin is slightly larger. It's easier to see the switches when you know what's pushing them.
I can answer some of that. First, if there is no SD card in the camera, it will appear dead -- opening and closing doors and inserting the battery does nothing. If there's a flash card installed, any time you either open or close either the battery door or the SD door, the red led will flash. You can't get to either door switch (the actual switch) without opening the camera but you can see the little detente on each door that pushes the switch. If a detente breaks off, that could cause apparent death.
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I can answer some of that. First, if there is no SD card in the camera, it will appear dead -- opening and closing doors and inserting the battery does nothing. If there's a flash card installed, any time you either open or close either the battery door or the SD door, the red led will flash. You can't get to the connections of either door switch without opening the camera but you can see the little pins (detents?) on each door that push the switches. If a detent breaks off, that could cause apparent death.
+
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NOTE!! (I have a working T3i and tried and verified this.) If you insert a dead SD card (I used an microSD adaptor with no card), the LED will NOT blink and removing that and inserting a good SD card WON'T FIX IT -- the camera appears to be dead. If you then remove and re-insert the battery (and if you're quick enough you won't lose your configuration), the camera works normally -- flashes when either door is opened or closed. There is indeed an SD door switch (as Tony said), but the camera evidently reads the SD before flashing the light. So, if your camera appears to be dead, try a new/better SD card.
+
+
Irisheyes and Dana ask where the switches are. Tony was talking about the pins on the doors that push the switches. The battery-compartment-door pin is right below the arrow printed on the inside of the door -- opposite the hinge, toward the center of the camera. The SD-card-door pin is opposite the hinge, toward the bottom of the camera. The SD-door pin is about 0.1" x 0.05"; the battery-door pin is slightly larger. It's easier to see the switches when you know what's pushing them.
I can answer some of that. First, if there is no SD card in the camera, it will appear dead -- opening and closing doors and inserting the battery does nothing. If there's a flash card installed, any time you either open or close either the battery door or the SD door, the red led will flash. You can't get to either door switch (the actual switch) without opening the camera but you can see the little detente on each door that pushes the switch. If a detente breaks off, that could cause apparent death.