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Discussion Starter #1 (Edited)
I have been looking for a suitable delay timer ever since I installed a replacement aftermarket backup camera in my MY2013 and discovered I had the "black screen syndrome". I found a number of relatively large board timers with push buttons and displays that might work, but were certainly not suitable for a wired in automotive application. After a fairly extensive Internet search, I finally found an affordable and rugged delay timer to eliminate the black screen that occurs for several seconds when you shift out of reverse. This problem usually occurs after either adding a backup camera to a car that did not have one, or replacing the less than stellar factory one with an aftermarket unit.

It turns out that the factory camera (at least on my 2013 Volt) Has two power inputs: one labeled "IGN" on the schematic, that is on whenever the car is on, and a power line which is directly connected to the backup light circuit. The factory camera contains a built in timer which keeps the camera turned on for about 20 seconds after the backup lights turn off. The center console monitor keeps the backup view for about 5 seconds after you shift from reverse to a forward gear. If you have an aftermarket camera without the timer, it turns off with the backup lights and the screen will be black for those 5 seconds.

The timer I found is very small and very capable, but has a huge name. It is called "Small Miniature time on off cycling delay relay 0.1 sec to 9999 hours. 5V 12V 18V DC 5A. Power On Off delay, Cycling. Industrial control and hobby" That's the official name on Amazon. The manufacturer just calls it a "Multi-functional Timer". It sells for just under $20 including shipping, it doesn't qualify for Prime.

There are 20 different timer modes available, selected by a somewhat complex programming process, however with the excellent online manual and detailed videos for programming each timer mode, it only takes a few minutes to understand what needs doing, and usually under a minute to actually do it. Once you program the unit, It remembers what to do until you program a different mode. What we need for the backup camera delay is program mode 12. This will result in the camera being powered on instantly upon it seeing the backup light power. As long as the light is on, the camera is on. When the light goes off, the camera will remain on for whatever additional time we programmed. I am using around 10 seconds. Obviously, if your screen stays black for longer than 5 seconds, increase this time. The biggest downside to using this timer is that for most of us it means pulling one side of the rear bumper to gain access to the camera and its connector. If you previously routed a separate wire from the BCM to the camera, you can install the timer anywhere along this wire where you have access to Ignition power and ground.


This is the timer. As you can see by the size of the pen, it is quite small.



I just finished installing this timer in my MY2013. In a previous post http://gm-volt.com/forum/showthread.php?264737-I-just-replaced-the-backup-camera-on-my-2013 I go through the process of changing the factory camera for an aftermarket one with a wonderful improvement in resolution and shading, (but unfortunately I had the "black screen syndrome"). Today I removed the rear bumper again and removed the camera and cabling. On the bench I rewired the harness between the connector and the camera, installing the timer into the circuit. I guess practice makes you faster. I removed the bumper and had access to the camera in about 10 minutes. In another couple I had the camera and harness out.


On the left is the timer wired into my camera harness. I tied it in right at the connections to the cut harness near the connector. On the right is the harness after using a short length of loom to tidy things up.




Here is the camera and harness installed in the car. You can see the timer hanging out the end of the larger diameter loom.



After re-installing the camera harness, I tried shifting to reverse then to drive. The camera image was on until the display changed - NO MORE BLACK SCREEN!

In case you are interesting in installing one of these timers to your aftermarket backup camera, I am including the programming and the connections needed. If you have no interest in that, you may quit now.

Programming:

First make sure to read the online manual at bit.ly/timer17.com and watch at least the video for programming mode 12. Note that on the video he uses a different trigger mode to activate by grounding the trigger wire. Since our backup lights go to +12 volts, we need mode 2, not mode 4 as he demonstrates.

Set the timer up on the bench. Make the Red wire available to connect to +12 volts, but don't connect it yet (a switch for this is handy. If you are using a power supply, its switch will do fine.)

Connect the Black wire to Ground (the minus side of the 12 v)

Connect the Yellow wire to a 12 volt load that draws less than 5 amps, like a small light bulb with the other terminal grounded.

Leave the Blue wire disconnected for now, but insulate the end with a piece of tape just in case.

The White and Green wires will be floating, but connected to ground as called for to program the timer. You can do this by just touching the wires to ground, or actually wire in push buttons. As you will be just doing this once hopefully, just touching the wires should be fine.

Step 1
Connect both White and Green wires to ground, then connect the Red wire to +12 volts. About a second later, unground the White and Green wires. The indicator light should light for 3 seconds to show the timer is in programming mode.

Step 2
Ground the White wire for the period of time you want to delay the turning off of the camera. I suggest at least 10 seconds. The timer measures how long you ground the wire and sets that as the time. There is a more complicated procedure to set the timer for a precise time from 0.1 seconds to thousands of hours, but we don't need to do that.

Step 3
Momentarily ground both White and Green Wires. This sets the unit to program the timer mode and the trigger mode.
We want timer mode 12, so ground the White wire 12 times. The light should flash briefly each time.
We want trigger mode 2, so ground the Green wire 2 times and the light will flash a shorter flash each time.

Step 4
Turn off the power to the Red wire. Programming is complete.

Test the programmed timer by turning on the power to the Red wire. Nothing should appear to happen. Now connect the Blue wire to +12 volts. The light should light for as long as the Blue wire is connected and stay lighted for about 10 seconds longer. If it does this, you are ready to install it.

The timer is about the size of a nickel and has 6 colored wires. After programming, connect the wires as shown. Note that the white and green wires are not used and should be insulated. They are used only for programming.



On the left is the minimal needed schematic. It will work just fine. If you are a "belt and suspenders" type like I am, you may want to add the two diodes shown in the right schematic. The only function of them is to ensure that the camera will still come on with the backup lights no matter what happens with the timer. While I have the utmost trust that the timer will keep working, it's a lot of work to access the camera if it doesn't.


That's all there is to it. Your camera now acts just like the factory camera and stays on long enough to eliminate the black screen.

Just for the record, I have no connection with Amazon or 3rdbrakeflasher.com, the maker and actual seller of this timer. I'm just a happy customer who finally found a timer that works exactly the way we need for it to solve a problem.

Dick
 

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If you need a source of camera power after the backup light has turned off, you can do one of two other installations:

Add a capacitor and a diode to store some of the 12 VDC energy for the few seconds you need. The diode is placed to prevent the capacitor from discharging through the backup light after the power is removed.

Or use the 12VDC from the brake light as the second power source adding a diode so the brake lamp only powers the camera and not the backup light. Since everyone steps on the brake to shift from Reverse to Drive, the brake lights can power the camera anytime, but if the display is on, you may have the extra benefit of seeing that rear view every time you do step on the brakes.
 

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Discussion Starter #3
If you need a source of camera power after the backup light has turned off, you can do one of two other installations:

Add a capacitor and a diode to store some of the 12 VDC energy for the few seconds you need. The diode is placed to prevent the capacitor from discharging through the backup light after the power is removed.

Or use the 12VDC from the brake light as the second power source adding a diode so the brake lamp only powers the camera and not the backup light. Since everyone steps on the brake to shift from Reverse to Drive, the brake lights can power the camera anytime, but if the display is on, you may have the extra benefit of seeing that rear view every time you do step on the brakes.
Raymond, The capacitor is a good thought, but the cameras I measured (similar to the one I installed) take from 85 to 120 ma. and require a minimum of 7.5 to 10.0 volts to operate. If you take the best case, 85 ma. allowing the voltage to drop to 7.5 volts, it would take a 50,000 mfd capacitor. I located several on Ebay ranging in price from $41 to $84, they are about the size of a Coke can. Yeah, I did briefly think of that option.

Of course, another viable option is to connect the camera to the ignition line and power it the total time the car is running. I considered this, but decided I did not know if these cameras, designed for the intermittent backup duty, would last.

Thanks for the comments.

Dick
 

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Awesome! I was wanting to do the same to my 2013... you have done at least one reader a kind service. :)
 

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Raymond, The capacitor is a good thought, but the cameras I measured (similar to the one I installed) take from 85 to 120 ma. and require a minimum of 7.5 to 10.0 volts to operate. If you take the best case, 85 ma. allowing the voltage to drop to 7.5 volts, it would take a 50,000 mfd capacitor. I located several on Ebay ranging in price from $41 to $84, they are about the size of a Coke can. Yeah, I did briefly think of that option.
Or just drive a low-current relay coil with a much smaller capacitor - while powering the camera's circuit with the relay's 12 volt output.
 

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Discussion Starter #7
Or just drive a low-current relay coil with a much smaller capacitor - while powering the camera's circuit with the relay's 12 volt output.
When I started this project several weeks ago, I went through pretty much all the ideas that have been brought up here. I started trying just a capacitor and camera, and the capacitor and relay, as you suggest. I have a pretty good junk box with 6 or 7 types of 12 v. relays ranging from DIP size to the heavy duty auto type. The coils draw from 51 ma. for the smallest to over 180 ma. for the automotive type. After trying a couple other ideas, I ended up designing and building my own timer using 7 components plus a relay a size larger than the tiny DIP size. I had pretty much finished testing it when I found the Multi Function Timer on Amazon. In my opinion it was better than my design in almost every respect. It was smaller, it was totally sealed, it was totally solid state, and I could change the delay time without changing any components. It was also probably cheaper than mine if I had to buy the parts, although they were all from my junk box. At less than $20 I bought it.

My design, as long as I am talking about it, consisted of 7 components plus a relay. I built it on a small piece of perf board and used a cell phone power supply case to house it. It had a reliable 13 second delay time. It works by the B/U light circuit charging a capacitor through an isolating diode and a current limiting resistor. This turns on an NPN transistor which pulls in the relay. When the B/U lights go off, the capacitor discharges through a resistor and the base of the transistor. When the voltage of the cap is too low to keep the transistor turned on, the relay drops out. I also have an extra diode to bypass the timer in case of any failure.


The parts all fit on a small piece of perf board.




It slips into the case from a cell phone charger and is held/cushioned by foam.




It is a pretty secure package with the cover on. I have not sealed it yet (or probably ever now).




Here is the schematic of what I came up with if anyone wants it.


I had fun designing, building, and testing it, but I still feel the purchased one is better!

Dick
 

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Discussion Starter #8
OP Missing Photos

For some reason the photos from my original post have disappeared. I am reposting the photos here:


This is the timer. As you can see by the size of the pen, it is quite small.




On the left is the timer wired into my camera harness. I tied it in right at the connections to the cut harness near the connector. On the right is the harness after using a short length of loom to tidy things up.




Here is the camera and harness installed in the car. You can see the timer hanging out the end of the larger diameter loom.



Programming:

First make sure to read the online manual at bit.ly/timer17 and watch at least the video for programming mode 12. Note that on the video he uses a different trigger mode to activate by grounding the trigger wire. Since our backup lights go to +12 volts, we need mode 2, not mode 4 as he demonstrates.


On the left is the minimal needed schematic. It will work just fine. If you are a "belt and suspenders" type
like I am, you may want to add the two diodes shown in the right schematic. The only function of them is to ensure that the camera will still come on with the backup lights no matter what happens with the timer. While I have the utmost trust that the timer will keep working, it's a lot of work to access the camera if it doesn't.



Sorry for the confusion.

Dick
 

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Retained Accessory Power is available at the lighter socket between the rear seats. Technically you'll be wasting a bit of juice by keeping the camera powered on whenever the car is on, but you won't have to worry about the camera shutting off early. If you're replacing an existing OEM camera, you could just use the IGN power that's already there instead of the backup light connection (non-camera cars don't even have the fork off the backup light, so I doubt they have the IGN either - I didn't notice it when I installed my camera).

I'd love to see someone donate their OEM camera for dissection to see how the delay is done in that unit.
 
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