Android Radio Unit Can-Bus draining battery

[diegoiua]

Hi everyone,

 

recently I've bought one of these Chinese Android radios for the Fabia mk3 from my wife, so that she can get navigation and, most importantly, rear view camera :).

After creating myself the removal tools for the original radio as these were not provided with the Chinese one, I proceeded to install the new one with the cables provided.

The radio comes of course with the Can-Bus emulator box.

 

I mus comment as well that the radio was provided with two ISO adaptors, one for "Golf IV" versions and another for "Passat" versions. I installed it the first time with the Golf VI version, although I was not sure which one was the right one.

 

Anyway, before installing it I've noticed that both the radio and the can-bus box were drinking the main current from the same yellow cable, and there was no second red cable as usual (the one that you should disconnect if you do not want the radio to suck your battery when the car is turned off). So I assumed that by default either the radio was shutting off the current automatically (via can-bus) or the source of current was shut-off by the car.

 

Fool of me, on this first installation I haven't checked the current consumption with the car turned off, and as the car has been stopped some days due to the quarantine, when we tried to start it again, the battery was dead.

 

So after some internet research, I've found out that the in the new VAGs there is no longer 2 current lines arriving to the ISO adaptor, but only one which is always fed with current, independently of the position of the key. The shut-off of the original car radio happens through the can-bus signal. This means, that the original radio is always sucking some current to keep the minimum systems alert (turn on/off thru can-bus).

I haven't measured the original one, but I guess the current drain has to be minimal, perhaps less than 100mA, otherwise the battery would be dead pretty soon as well.

 

After the research, I proceeded to install again the radio with the second cable provided (the "Passat" version), to try again and, this time, measure the drain current, which happened to be 200mA.

I'm afraid I can't say if at the first installation (with the Golf VI cable) the drain current was the same, as I haven't had time to check both cables, but I shall assume that the current drain was either the same or higher, and it was enough to kill the battery after 4-5 days.

 

So I looked around to see if there was any power cable close to the radio to check if it was shut-off when I remove the ignition key so I can bridge the original ISO connector installation with a shut-off current source. The only thing close to the radio with enough current was the cigarette lighter, but this one as well is not shut-off with the key removal.

 

Therefore here my request for some help:

 

1. Does anybody know if there is any way to shut-off this current line adding some extra circuitry perhaps (a can-bus activated relay for instance)?
2. If the first option sounds too complex, does anybody know any current source line that I can take, perhaps directly from the fuse-box, that can handle the 2-5 Amps of the radio and it's being shut-off when removing the ignition key?

 

By the way, apart from this issue, the radio works pretty damn well and the integration with the dashboard is perfect. I couldn't try the functioning of the steering-wheel controls as my wife's Fabia doesn't have them, but I guess it should work as the radio does show other can-bus info, like the open doors.

 

Thanks in advance and stay healthy!

Cheers,

Diego

 

 

 

 

 

 

Edited 8 April, 2020 by diegoiua

[langers2k]

The total current draw for the entire car after it's been locked for 2 hours should drop below 40mA. The radio and it's CAN-bus adaptor should probably be under 20mA at a guess as it shouldn't take much current to listen for CAN-bus messages.

 

Might be worth asking the seller if they have a CAN-bus adaptor that's correct for your car as the MK3 Fabia is a different platform to the MK6 Golf or Passat.

 

I assume there is still a fuse box in the end of the dashboard? If so, I'd use a multimeter to find a ignition switched live and run a new wire to the headunit. I've no idea how well it'll work with the CAN-bus adaptor though.

 

Might be worth adding a link or at least a make/model for the headunit as it might give some clues...

[diegoiua]

3 hours ago, langers2k said:

The total current draw for the entire car after it's been locked for 2 hours should drop below 40mA. The radio and it's CAN-bus adaptor should probably be under 20mA at a guess as it shouldn't take much current to listen for CAN-bus messages.

 

Might be worth asking the seller if they have a CAN-bus adaptor that's correct for your car as the MK3 Fabia is a different platform to the MK6 Golf or Passat.

 

I assume there is still a fuse box in the end of the dashboard? If so, I'd use a multimeter to find a ignition switched live and run a new wire to the headunit. I've no idea how well it'll work with the CAN-bus adaptor though.

 

Might be worth adding a link or at least a make/model for the headunit as it might give some clues...

 

Ok, I will do the current check after 2 hours as you say.

 

Regarding the seller, I bought the unit from Aliexpress (HERE THE LINK) but I wouldn't recommend to buy from this seller.

They say there that the product will be delivered from Czech Republic, but it came from Germany. Then when I tried to contact them, they answered via Whatsapp from China.

And the support was really bad, they were not able to understand what the problem was, although I was sending them pictures.

 

According to the technical description, is an Rockchip PX3 Cortex A9 Android 9.0 based unit.

 

And where I wrote Golf mk6 should be actually mk7, I've just checked again the cable.

 

 

[J.R.]

The canbus adaptors just allow the radio to recieve and interpret data from vehicle speed, steering wheel controls, climatronic settings, steering angle (for reversing camera grid), it does not instruct the vehicle to switch off the power to the radio, the OEM radio clearly achieves this trick but it probably that the canbus recognises it as being present and knows to do so.

 

The solution is to fit and code a later variant of the canbus gateway which I did on my Octavia 2 with the desired result, the Yeti has a later one so works fine.

 

On both cars removal of the stock radio results in loads of fault codes and my experiments with the various options in VCDS only seem to have made matters worse.

[langers2k]

3 minutes ago, J.R. said:

The solution is to fit and code a later variant of the canbus gateway which I did on my Octavia 2 with the desired result, the Yeti has a later one so works fine.

 

A MK3 Fabia is nothing like a MK2 Octavia electronically and they do not share the same issue wth early CAN gateways with later headunits.

 

4 minutes ago, J.R. said:

The canbus adaptors just allow the radio to recieve and interpret data from vehicle speed, steering wheel controls, climatronic settings, steering angle (for reversing camera grid), it does not instruct the vehicle to switch off the power to the radio, the OEM radio clearly achieves this trick but it probably that the canbus recognises it as being present and knows to do so.

 

The CAN-bus adaptor is almost certainly creating a switched live to turn the headunit on/off with the ignition. I don't think the OP has mentioned if it's turning on/off with the key so I assume it's working normally.

 

Anyway, I think they have a Klyde KD-8011, not that it helps given their website: https://www.szklyde.com/skoda-android-car-dvd/57568198.html

 

Might be worth contacting them to see if they have any suggestions? You could also bench test the headunit if you have a 12v supply? Looking at the image below, there is probably a yellow, red and black wire on the headunit power connector which are 12v, switched 12v and ground. If nothing else it'll be easy to check how much current it consumes when it's turned off.

 

[diegoiua]

2 hours ago, J.R. said:

The canbus adaptors just allow the radio to recieve and interpret data from vehicle speed, steering wheel controls, climatronic settings, steering angle (for reversing camera grid), it does not instruct the vehicle to switch off the power to the radio, the OEM radio clearly achieves this trick but it probably that the canbus recognises it as being present and knows to do so.

 

In the mk3 (which is different in this to the mk2, I had one as well), the ONLY power cable that arrives to the ISO connector of your radio is always feeding current, no matter if the car is on or not, or even if the key is inserted or removed. The other cables on the connector are the speakers and the can-bus ones. Nothing else.

 

So if the can-bus is not switching off the radio, then what is it?

[diegoiua]

2 hours ago, langers2k said:

 

Anyway, I think they have a Klyde KD-8011, not that it helps given their website: https://www.szklyde.com/skoda-android-car-dvd/57568198.html

 

 

 

On the front looks the same, but on the back it doesn't.

 

 

2 hours ago, langers2k said:

 

You could also bench test the headunit if you have a 12v supply?

 

 

 

I did. Doing this I found out that if the can-bus is not connected, then none of the buttons of the front panel of the radio work. Only the touchscreen.

 

 

2 hours ago, langers2k said:

 

Looking at the image below, there is probably a yellow, red and black wire on the headunit power connector which are 12v, switched 12v and ground. If nothing else it'll be easy to check how much current it consumes when it's turned off.

 

 

No, there is only one power cable, yellow, which is the 12v permanent, and of course the black one for ground.

There is no switched 12v red, which is the typical installation that you find in almost all the radios so far. In fact, search for "android drain battery" in youtube and you find loads of videos showing the same solution: cut the red cable. Well, they forgot that in some cases there is no red cable.

 

There is however a thinner yellow and red coming out of the can-bus box, but I've tried cutting them (one at each time and both together) and the only result is the can-bus box no longer working, but the continues to drain the battery when switching off the car.

 

[diegoiua]

Anyway, I found my way through the problem by bringing a switched 12v line directly from the fuse box.

I marked in red in the picture below which like of fuses are switched 12v.

 

If you remove the two torx bolts, the fuse box drops enough to allow you to remove the back cover and access the fuses from the back, so you do not need to pin-in the cable from the front.

 

Then I added a 15A fuse to my cable, brought it up to the radio and I fixed it so it doesn't move around.

 

Finally, I removed the 12v pin (yellow cable) from the radio ISO connector and I connected it to the switched 12v cable that I brought up.

 

And problem solved! No more current drainage, as this line is immediately switched off when removing the ignition key.

 

 

Edited 8 April, 2020 by diegoiua

[alexcarr1029]

On 08/04/2020 at 17:51, diegoiua said:

Anyway, I found my way through the problem by bringing a switched 12v line directly from the fuse box.

I marked in red in the picture below which like of fuses are switched 12v.

 

If you remove the two torx bolts, the fuse box drops enough to allow you to remove the back cover and access the fuses from the back, so you do not need to pin-in the cable from the front.

 

Then I added a 15A fuse to my cable, brought it up to the radio and I fixed it so it doesn't move around.

 

Finally, I removed the 12v pin (yellow cable) from the radio ISO connector and I connected it to the switched 12v cable that I brought up.

 

And problem solved! No more current drainage, as this line is immediately switched off when removing the ignition key.

 

 

Do you think this can be done on my Octavia 2 2007, mine will have the same issue if I fit mine 

[langers2k]

8 hours ago, alexcarr1029 said:

Do you think this can be done on my Octavia 2 2007, mine will have the same issue if I fit mine 

 

If you fit a headunit that uses CAN-bus, there is a chance you'll end up with battery drain as it's pretty common on older MK2 Octavias such as a 2007.

 

If you fit a headunit that needs a switched live, you will need to run one from the fusebox as the standard quadlock does not include one.

[chiku]

On 08/04/2020 at 22:21, diegoiua said:

Anyway, I found my way through the problem by bringing a switched 12v line directly from the fuse box.

I have the same problem. Could you please explain this step.