Citroen C4 II Aftermarket Radio

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nemanja066
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Citroen C4 II Aftermarket Radio

Unread post by nemanja066 »

Hi,

I recently installed chinese android head unit. Everything works fine, but my battery is leaking when the car is turned off. The problem is probably related to the canbus network and communication, it is not a problem with the drain of head unit power supply. The battery leaks as soon as the OEM radio is removed. Is there a possibility to use Diagbox and set it (in BSI configuration maybe), no longer have a radio device? Would that work properly?
I don't have a diagbox yet, it should arrive from China soon.

Thanks
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GiveMeABreak
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Re: Citroen C4 II Aftermarket Radio

Unread post by GiveMeABreak »

You could try that, but just remember to record all previous values before you change anything!
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Marc
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GiveMeABreak
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Re: Citroen C4 II Aftermarket Radio

Unread post by GiveMeABreak »

It may be constantly searching for the old radio that it has been told was there which may be the drain. These are live even when the ignition is switched off. Either that or you have the wrong CAN connection / harness for the new unit.
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Marc
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Re: Citroen C4 II Aftermarket Radio

Unread post by wheeler »

Are you saying the battery is draining just when the radio is unplugged before you plug in the new unit? then it is normal again if you re connect the original radio?
What amp draw reading are you getting with & without the radio plugged in?
This doesn't sound right, even if it does look for the radio i would expect it to give up after a few minutes when the network goes to sleep.

I have fitted plenty of aftermarket radios to full CAN vehicles & i never un program them from the BSI either (just to make it less hassle if the original radio has to be re installed), you will get some communication fault codes logged in the instruments & MFD etc but never had any battery drain issues.
nemanja066
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Re: Citroen C4 II Aftermarket Radio

Unread post by nemanja066 »

No battery leaks with OEM radio only. The aftermarket radio is well connected. It's simple, +12V from the battery is connected, and there is ACC output from the canbus decoder. 8 wires for speakers and 2 for canbus (Can Data H and Can Data L). The voltage on these CAN wires must be around 0V when the car is in sleep mode, but it is not, there is some voltage. I read that some have this problem and some don't, it depends on the version of the CAN gateway. supposedly the new version of can gateway solves the problem, but I would bypass that (because it is not available) and try to solve it via Diagbox.

I think the problem is in the communication (canbus network), BSI does not receive the information that the radio is off and cannot go to sleep mode. With the OEM radio, I measured the current with current clamps on the battery terminal and it is about 1-2mA, and with the aftermarket about 150 mA. I will definitely scan with Diagbox to see what errors it will display. I was most interested can it be solved in the way I imagined (BSI configuration - AutoRadio - Absent).
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GiveMeABreak
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Re: Citroen C4 II Aftermarket Radio

Unread post by GiveMeABreak »

I would agree with that regarding sleep mode - if there's activity on the data network, then it won't go to 'sleep' for some time, causing a drain; same with a BSI reset, not shutting all the doors to allow the data networks to sleep as an example.
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Marc
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Re: Citroen C4 II Aftermarket Radio

Unread post by wheeler »

nemanja066 wrote: 21 Mar 2025, 17:07 The battery leaks as soon as the OEM radio is removed.
Absolutely, but i was basing my thoughts on this above. The OP suggested that the drain starts as soon as the original radio is removed , no mention of installing the new unit.
I did ask for confirmation of this as that just did not sound right.
If the drain starts when the new head unit is connected then yes it may well be stopping the network going to sleep.
Also there is no guarantee that un programming the radio from the BSI will stop this, the new radio may be sending random messages on the CAN that will keep it awake.
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GiveMeABreak
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Re: Citroen C4 II Aftermarket Radio

Unread post by GiveMeABreak »

Yes, absolutely - and why I mentioned a possibility of the incorrect CAN interface / harness for the new unit.
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nemanja066
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Re: Citroen C4 II Aftermarket Radio

Unread post by nemanja066 »

The same battery drain exists with the aftermarket radio connected, and when nothing is connected (everything is disconnected). Only with the oem radio everything is fine. The aftermarket radio has a canbus decoder, so it only receives and decodes information from the canbus network and sends it to the unit, I'm not sure if it can send something over the network and communicate.

Connection of head unit is very simple, plug and play, it is impossible to make a mistake. I tried 3 different canbus decoders (manufacturers) , everything is the same.

I also post pictures of the connectors (pinout) if needed.
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nemanja066
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Re: Citroen C4 II Aftermarket Radio

Unread post by nemanja066 »

Just to let you know that I solved it. This is the solution (Without Audio System & Absent). Now, BSI doesn't report any errors in communication with the radio device and probably goes into power save mode properly.
All is working fine. Thank you all for your help.
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