HK3 does not resume power after reconnecting car battery

mituc

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Dash Cam
2xITB-500HD,3xVico Opia 2,Mini 0906,70MAI A800S, A129ProDuo
Before ordering another HK3 power kit thinking that mine has a problem I'd like to know if anyone else noticed if the power module starts providing power as expecting after resuming power on the Battery (red) cable.

In my case I noticed the following behavior: if I disconnect the car battery and reconnect it back the HK3 will not resume power unless I turn the car back on so that the HK3 will receive a signal on the ACC (yellow) cable even for a fraction of a second. Once that happens I can turn the car off and the parking mode will continue as expected.

Is this how the HK3 module works or it's just mine acting weird?
 
Probably below the voltage threshold for turn on, which is higher than the one for turn off.
 
Yes, it's like that by design.
 
Probably below the voltage threshold for turn on, which is higher than the one for turn off.
Actually the battery I'm using at the parking facility has an output of 13.2V or higher.

Yes, it's like that by design.
Ok, so it won't make any difference if I will buy another one.
Well, even this camera had to have something that would not make it totally right. The power module and the freaking massive cables and mini-usb connectors which made the install a nightmare.
 
Actually the battery I'm using at the parking facility has an output of 13.2V or higher.


Ok, so it won't make any difference if I will buy another one.
Well, even this camera had to have something that would not make it totally right. The power module and the freaking massive cables and mini-usb connectors which made the install a nightmare.
it's working as intended, what's the usage scenario where you want to disconnect power and reconnect power anyway?
 
Actually the battery I'm using at the parking facility has an output of 13.2V or higher.
Lead acid batteries don’t go up to 13.2 volts, except while charging, and definitely don’t after a little discharge.
 
Ok, so I had an exchange of emails with the VIOFO support and it seems that indeed the power module is designed not to turn on when the car battery is reconnected. It looks like they designed the module itself with this major flaw in it. this is absolutely mind blowing... One of the best of the few decent 4k cameras on the market and besides the absolutely massive cables making it a nightmare to install without butchering the headliner and trims had to have an absolutely stupid design flaw that would prevent the parking mode hardwire kit from recording when the car is parked defeating basically its own purpose.

I will splice the cables and see what wires go where and replace the HK3 with the 70MAI hardwire module.

Lead acid batteries don’t go up to 13.2 volts, except while charging, and definitely don’t after a little discharge.
It happens the same if I disconnect and reconnect the car battery. As I mentioned that 13.2V power supply is from a long therm parking battery. It actually doesn't matter, the power output can be anywhere from 11.8V which is the low threshold on the HK3 and up to 14.6-14.8V or whatever the alternator output is at full speed before entering in bypass mode. So the voltage is not a problem. The module not coming back after starting to receive again power on the BATtery cable is the actual huge problem.
 
Ok, so I had an exchange of emails with the VIOFO support and it seems that indeed the power module is designed not to turn on when the car battery is reconnected. It looks like they designed the module itself with this major flaw in it. this is absolutely mind blowing... One of the best of the few decent 4k cameras on the market and besides the absolutely massive cables making it a nightmare to install without butchering the headliner and trims had to have an absolutely stupid design flaw that would prevent the parking mode hardwire kit from recording when the car is parked defeating basically its own purpose.
I'm probably missing something, in which part do you see the flaw or what prevents your cam from recording in parking mode?

It sounds to me more like you are trying your special usecase and the function of the HWK is not suitable...


Btw: It's "HardWireKit" you can't expect the manufacturer to expect that somebody will try not hardwiring it...
 
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I'm probably missing something, in which part do you see the flaw or what prevents your cam from recording in parking mode?
The flaw is that the HK3 does not do its job of providing power to the camera even if it receives power in a proper way. The function of these hardwire kits is simple:
  1. if power comes on both BATtery and ACCessories cables - power the camera and signal it is in driving mode;
  2. if power comes only on the BAT cable - power the camera and signal the camera it is in parking mode;
  3. if power comes only on the BAT cable and the input voltage is below the set threshold (11.8V in my case) then cut the power to the camera to prevent the car battery from being drained.
It is that simple.

In my case the HK3 fails at #2 when reconnecting the car battery. To make it work properly again in mode #2 I have to go through #1 (turn the car on and then off - no need to start the engine just put the key to into the ACC position).
When this is necessary apart from the common sense "all the time":
- in my case when reconnecting the car battery;
- in any other situation when the car battery is worked on and reconnected, such as a car shop.
 
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In my case the HK3 fails at #2 when reconnecting the car battery. To make it work properly again in mode #2 I have to go through #1 (turn the car on and then off - no need to start the engine just put the key to into the ACC position).
When this is necessary apart from the common sense "all the time":
- in my case when reconnecting the car battery;
- in any other situation when the car battery is worked on and reconnected, such as a car shop.
Why would you want to "reconnect" your battery? (except the example with carshop) BAT wire should be connected to the battery (continuous power source no matter in which state your car is) and the only wire which should be connected/dischonnected from the power is ACC, based on which your cam gets the signal whether car is parked or active.

Then only after the "first" connection to battery HWK doesn't provide power, next time it will work right away, until you disconnect the BAT wire and then it again needs the first initial ACC connection.
 
Why would you want to "reconnect" your battery?
I don't think it really matters. If the power kit receives power on the battery wire and the voltage is above the minimum threshold it should work as advertised and provide power to the camera. This is what parking mode is, no matter if the battery was reconnected or not after stopping driving.
 
Well, simply, it's not the case for Viofo's HWK. As mentioned above, it needs the initial ACC connection to make it work as expected after every battery reconnection.
 
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As mentioned above, it needs the initial ACC connection to make it work as expected after every battery reconnection.
Yes, I know now and I understand how it works.
But this is a faulty design and not compatible to all situations when a car is parked. As an interruptible power kit it should provide uninterrupted power unless the power cut conditions are met (no power at all, or power only on the battery cable and below the low threshold). Having an initial input on the non-permanent (read "interruptible") input should not be a condition to provide uninterrupted power.
 
I'm finding the disconnection of the battery when parked a little surprising. Is this whilst in storage and to preserve the battery?
I store my car for some periods but dont disconnect the battery but do keep it charged by attaching a trickle charger for periods during storage. Is it usual where you are to disconnect the battery and replace it with an alternate supply, and would be interested to know what are the benefits?
 
Yes, I know now and I understand how it works.
But this is a faulty design and not compatible to all situations when a car is parked.
I don't think you do understand, if the camera was last connected by three wire power disconnecting and reconnecting the the B+ won't turn the camera back on, the ACC needs to be triggered, it's not a faulty design, it's an intentional choice

if the camera was connected by 2 wire power disconnecting and reconnecting will turn the camera back on

the logic that controls this is in the camera, not the hardwire kit
 
I don't think you do understand, if the camera was last connected by three wire power disconnecting and reconnecting the the B+ won't turn the camera back on, the ACC needs to be triggered, it's not a faulty design, it's an intentional choice
As I mentioned before I perfectly understand how it works. I described the behavior from the very beginning. However because as stated above I don't think this is compatible with all parking situations at first I saw this as a defect. Now I see it as a design flaw which I never came across so far with any parking surveillance setup.

the logic that controls this is in the camera, not the hardwire kit
No, it's actually the hardware kit that stops providing power unless it is triggered again on the ACC wire.

I implemented a way around it, so it doesn't matter any more.
 
there's a combination of logic in the firmware to look for the same power source it was previously connected by, 2 wire or 3 wire, and the hardwire kit will shut back down when not required, it's not a flaw or a defect it's a feature, some cars have circuits that wake back up periodically, if connected to one of these the camera would come back on and start recording randomly
 
it's not a flaw or a defect it's a feature, some cars have circuits that wake back up periodically, if connected to one of these the camera would come back on and start recording randomly
I guess it's a matter of perspective. But if you ask anyone who needs and is using parking mode I'm sure you will find out two things that will not comply with your statement:
  1. I'd have a full resolution full length video every few hours when that circuit wakes up rather than not having parking mode at all;
  2. there is absolutely no point in implementing a safety "feature" that will power the camera down entirely in certain situations just because the user may tap into the inappropriate circuit. If someone installs it wrong then whatever, but when installed properly it should perform accordingly.
For supporting those two mentions above I'd say (and this is my opinion): I'd like to have parking mode also after, say, working on the car but didn't have time to start it since at that point the car is still parked so I'd expect parking mode to work if the camera is installed correctly with the price of having the 256GB SD-Card willed with1GB of footage instead of just 100MB for the same time interval every few hours in case I wired the ACC connection of the power module of the camera from the wrong circuit instead of a true ACC(essories, or contact) circuit as stated in the camera manual.

I get your logic though, just that in my opinion parking mode should not be available only when parking the car after driving it because it is not limited to that. A parked car means a car that is not being used at that time, not only a car that executed a parking maneuver and had the engine shut off for a few minutes.
 
I still am not understanding your need to regularly disconnect the vehicle's battery... but am interested to know!
 
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