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Discussion Starter #1
Hey Folks

Those of us with a factory fitted RNS 510 head unit are plagued with the unit auto powering off after 20-30mins when the engine is off. A real pain whilst parked/camped up.

From what i understand, the unit is instructed to power down via the CAN bus.
So supplying power to the head-unit via a leisure battery will not solve the auto power off issue.

So...
is there anyway around this problem?

Would adding a switch to the CAN bus' input (high/low) provide a way to optionally stop the 'OFF' signal being received, keeping power to the head unit work?

also, doesn't the head unit remain on whilst parked/camped up when playing a DVD? if so, could we utilise this feature to prevent power down?


appreciated
at0m
 

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If it's like the RCD310, there is probably a way to code the radio itself with a different timer value. I did this with mine and IIRC (it was 4 years ago now) the maximum value was 59 minutes. Unfortunately it's not a documented modification (or it was not at the time) so I had to find it by trial and error.

The temporary disconnection of both CANbus wires might achieve what you want - I think disabling just one will not, as IIRC the bus can operate at reduced speed over just one wire.
 

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Discussion Starter #3
Thanks triffic

Good to know there is/could be a way around this.
Did you use vagcom to find/amend the values needed?

I've poked various memory locations using SetRegDataHex function + boot disc. But its far too crude a technique to reverse engineer the issue.

Would you (anyone) know. Does the head unit remain on whilst playing a DVD parked up?

Now wondering if i could use Multi-pin connector 5, audio and video, to provide an audio source keeping the unit on!?
 

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Discussion Starter #6
before adding a switch to the CAN bus' input, i guess the question is;

does the CAN bus tell the head unit to shutdown, or does the head unit power itself down after a defined time

intuition says "head unit powers down after defined time"
but i'm not sure how to test this theory

on a side note;
do factory fitted RNS 510's in factory fitted campers have the same issue?

:*
 

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As I understand it, the ECU (or Central Electronics) broadcasts a message over CAN saying "Engine Off" and the radio starts an internal timer. Hence you need to code changes (if you want to fix it that way) in the radio, not elsewhere.
 

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Discussion Starter #8
It defiantly makes sense that the value is stored on the head unit, as turning on the unit manually must start this timer.

Based on that logic, adding a switching to the CAN bus source is not going to solve the timeout
 

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Discussion Starter #9
Last night i tested if the head unit times out from these sources: DVD, CD, SDCard and Hard Drive
The timeout issue/feature affects all the above, even DVD Video!

This is leaving me very puzzled;
By default the head unit will not play a DVD whilst in motion, and when stationary the head unit will only remain on for ~20mins.

How does anyone watch an entire DVD, without turning the unit back on!?
 

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Want Electrics? Go Wildebus!
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Hey Folks

Those of us with a factory fitted RNS 510 head unit are plagued with the unit auto powering off after 20-30mins when the engine is off. A real pain whilst parked/camped up.

From what i understand, the unit is instructed to power down via the CAN bus.
So supplying power to the head-unit via a leisure battery will not solve the auto power off issue.

So...
is there anyway around this problem?

Would adding a switch to the CAN bus' input (high/low) provide a way to optionally stop the 'OFF' signal being received, keeping power to the head unit work?

also, doesn't the head unit remain on whilst parked/camped up when playing a DVD? if so, could we utilise this feature to prevent power down?


appreciated
at0m
"also, doesn't the head unit remain on whilst parked/camped up when playing a DVD?". Until it times out OR you take the key out the ignition (whichever comes first)
 

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Discussion Starter #11
@Hoovie

You have a wealth of electrical and audio knowledge/experience, is what i'm trying to do achievable without buying an after market head unit?

Do the factory fitted california's have the same issue/feature?
 

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Want Electrics? Go Wildebus!
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@Hoovie

You have a wealth of electrical and audio knowledge/experience, is what i'm trying to do achievable without buying an after market head unit?

Do the factory fitted california's have the same issue/feature?
I would think you would have to do something along the lines of what Triffic is saying and re-engineer the unit! Maybe try and spoof an "engine running" signal!!
All designed to work in a battery-saving mode (my own factory head unit in my DS5 does exactly the same thing but maybe only gives me 10 minutes of engine-off time :( ).
I don't know about the California units, sorry (but I suspect it will have the same issue).
 

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Discussion Starter #13
Thanks both for your input

Spoofing the CAN bus had occurred to me, i have looked into using a raspberry pi with CAN bus shield, but was unsure the power consumption knock on for other devices that remained awake.

Another approach would be to run another amp and have these share the van speakers

things to investigate
- acquire and use VCDS to find/change the head unit timeout value
- spoof the "engine on" signal over the CAN bus
- install additional amp linked to van speakers

Not the most accessible to-do list!

I'll keep this thread updated when/if i have progress


Anyone else got an angle ?


bluetooth speaker it is then :p
 

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Thanks both for your input

Spoofing the CAN bus had occurred to me, i have looked into using a raspberry pi with CAN bus shield, but was unsure the power consumption knock on for other devices that remained awake.

Another approach would be to run another amp and have these share the van speakers

things to investigate
- acquire and use VCDS to find/change the head unit timeout value
- spoof the "engine on" signal over the CAN bus
- install additional amp linked to van speakers

Not the most accessible to-do list!

I'll keep this thread updated when/if i have progress


Anyone else got an angle ?


bluetooth speaker it is then :p
We are in the process of designing a leisure switch setup for the factory headunit... as Triffic states the unit switches on/off by the CanBus, so DO NOT interfere with the CanBus wires....
The headunit times itself off
 

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Discussion Starter #16
I understand your warning re: disconnecting the CANbus, however, if the head unit is controlled via CANbus, wont breaking that connection (temporarily) be the only way to stop these signals turning on/off the unit?

Also, when turning the unit on manually (power button) does the CANbus get involved?

As you can tell, i've been wrestling this conundrum for some time and want to gain an understanding of this mechanism
Are there any resources that would help, stop me asking stupid questions?

cheers
 

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I understand your warning re: disconnecting the CANbus, however, if the head unit is controlled via CANbus, wont breaking that connection (temporarily) be the only way to stop these signals turning on/off the unit?

Also, when turning the unit on manually (power button) does the CANbus get involved?

As you can tell, i've been wrestling this conundrum for some time and want to gain an understanding of this mechanism
Are there any resources that would help, stop me asking stupid questions?

cheers
CanBus switches it on/off with the key and if it has a MFSW factory parking sensors and info on the MFD it does this also

Manually switches it on is nothing to do with the CanBus.... as it's just the radio which does this...
 

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Discussion Starter #19
Dont jump too soon, Absolut5 will save us all!

Seems like a multitude of hurdles to leap, wrangling messages on the CANbus (or maybe more specifically the Navigation Control Module) and controlling the timeout values used by the headunit to auto power off

Maybe once the product is at market, Absolut5 would be happy to share how it works, and maybe more interestingly, techniques used to reverse engineer the solution.

/me puts hand up for beta tester
 

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Discussion Starter #20
Found the official wording for the feature we are discussing

-------------------------------------
Switch-off time

If you turn off the ignition while the radio/navigation system is switched on or switch on the system without
“Ignition on”, the RNS will remain active for a further 30 minutes and then automatically switch off.
This function was previously called hour mode or hour logic.
The switch-off time of 30 minutes also applies to the simple Volkswagen radio models from model year 2008.
-------------------------------------

source: SSP 397-part2
 
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