How to keep radio on in 2020 Unity after parking?

mikescha

New member
We very recently took possession of a new 2020 Unity MB with the updated chassis. This unit has only one audio system, which is the one on the dashboard. We like to listen to music in the evening, so we park and turn off the engine, turn on Accessory mode, and start playing music over Bluetooth. So far, so good.

The problem is that the Accessory mode turns off automatically after about 15 minutes, at which point we have to go turn on Accessory mode again, and restart the music.

Is there a way to force the audio to stay on longer?
 

Rock Doc

Active member
I strongly recommend being cautious about this. I’ve wired my automotive stereo system so that I can switch between my automotive battery or my coach battery to power the in-dash stereo system. However, I’ve also noted that the stereo system pulls a LOT of amperage (which translates to a lot of amp-hours), and it’s a SIGNIFICANT power draw that can draw down your battery shockingly quickly. (Pun intended.) So, it can be used for shorter periods or I can use it this way via the converter when I’m plugged into a 120vac source, but I won’t use it for any extended time without watching the battery monitor. That in-dash stereo can be a real power hog, which is why it’s generally on an ignition circuit with a timer.

Just be careful!

Rock Doc
2014 Pleasureway Plateau TS in 2013 Sprinter 3500
 

Meeks

Member
My understanding was that there would be a bluetooth soundbar with the TV that you could use for your "house" audio.
 

Natuzzi

Member
My understanding was that there would be a bluetooth soundbar with the TV that you could use for your "house" audio.
Exactly what I would suggest. The soundbar should turn on by itself (without the tv) and then just Bluetooth your music to the soundbar.
 

mikescha

New member
I had assumed the soundbar only worked with the TV but that was definitely wrong! I found the button on the remote to switch to Bluetooth, and then paired my phone in less than 30 seconds. Now, we're rocking out in OKC waiting for a thunderstorm to pass!
 

Meeks

Member
I had assumed the soundbar only worked with the TV but that was definitely wrong! I found the button on the remote to switch to Bluetooth, and then paired my phone in less than 30 seconds. Now, we're rocking out in OKC waiting for a thunderstorm to pass!
Now you're talkin'! Or singing :).
 

blue

2011 LTV Unity CB
You should still heed the advice of Rock Doc in Post #2 unless you have shore power. I expect the soundbar will draw a lot of current and pull down your batteries.
 

Peter Tourin

2020 Unity RL, ex 2012 Unity MB
FWIW - I have an older MB - my dash stereo is rated 5-7 amps but actually draws about 2.1 amps. That's not so bad - you'd blow 21 Ah over a 10-hour night if you forgot to turn it off. But I've walked away from the RV for a few days and forgot to turn the radio off (on my year the radio has to be on to see the backup camera; easy to forget) and taken my batteries way down. Word to the wise...
 

kmay

2013 Unity MB
Not sure how long I could operate my stereo system. We listened to it for 4 - 5 hours and had no problems starting the next day. I showed a service porter how to turn on the radio and rear camera just trying to be nice and maybe avoid a problem. Insert clown noise here.

The hapless porter left the system on and somehow had activated the interior cab light. Dead battery. Interestingly, it seemed okay as I turned the key through the initial cold start procedure. Found out later the glow plug and fuel pump sequence pulls a lot of juice prior to engaging the starter.

Now I will connect a battery charger to the chassis when on shore power for more than a day or two. This seemed a good interim step to installing an automatic combiner/charger. I needed a battery charger with maintenance features anyhow for chassis and coach batteries.

Months later, I stopped at a very busy stand-alone Sprinter dealer in Orland Park IL (Chicago burbs). The cramped parking area was crammed with Sprinters. I asked the mechanic if he needed the rear camera. He laughed and said he'd maneuvered Sprinters in tight quarters for years with just the outside mirrors. I will no longer offer the camera.

BTW Orland Park MB/Sprinter is one of my favorites, great to see a stand alone sprinter with such a large shop.
 

kmay

2013 Unity MB
In response to the original question, maybe. Audio shops could easily move the audio power to an always on circuit, fuse and install a switch. What I don't know is how Mercedes Benz computer system currently "sees" the audio system and that part of the dash display. Or what a dealer would say about the change with regard to warranty. Since we are early in the product cycle, it may take the aftermarket audio folks a while to develop answers.
 

MichelPaulCote

New member
Spoke to Leisure travel vans. Their solution: via Wifi, stream radio stations and send to soundbar through a bluetooth media device. Expensive, complicated, and impissible when you are not within WIFI ou cell coverage (most of the time for us). Until Leisure travel van come to their senses re customer needs, here is the way to do it without changing the radio wiring.
1) buy a Sirius XM receiver (55$ in Canada) and install in compartment beside Wineguard booster and Sony player.
2) install a new Sirius roof antenna (20$) or Y into existing antenna and bring connector to Sirius device.
3) connect your Sirius device to soundbar via Sony media device.
Inexpensive, connected to coach batteries, you can listen to radio anywhere, anytime, without WIFI.
 

Daddy Dave

New member
The question has not been answered. How can I run my dash radio for longer than 15 minutes without the engine running? I agree there's a danger that I'll run down the battery.
 

Cheyenne

UK 2004 T1N 313CDi
The question has not been answered. How can I run my dash radio for longer than 15 minutes without the engine running? I agree there's a danger that I'll run down the battery.
Dave,

I think the question has actually been answered by the lack of an answer!

If anyone had managed it then they would have posted with the solution so it does not seem possible.

But I stand to be corrected if someone has actually managed to do it???

Keith.
 
Last edited:

2yrs2go

2019 Unity MB
Spoke to Leisure travel vans. Their solution: via Wifi, stream radio stations and send to soundbar through a bluetooth media device. Expensive, complicated, and impissible when you are not within WIFI ou cell coverage (most of the time for us). Until Leisure travel van come to their senses re customer needs, here is the way to do it without changing the radio wiring.
1) buy a Sirius XM receiver (55$ in Canada) and install in compartment beside Wineguard booster and Sony player.
2) install a new Sirius roof antenna (20$) or Y into existing antenna and bring connector to Sirius device.
3) connect your Sirius device to soundbar via Sony media device.
Inexpensive, connected to coach batteries, you can listen to radio anywhere, anytime, without WIFI.
Wouldn't this option require a separate Sirius XM subscription for the additional receiver? Also not a cheap solution
 

CharlieO

New member
Same problem with my 2016 Audio 15. I have used a fuse tap to "hot wire" the radio with power from the house battery but it still turns off after 30min. My house battery has plenty of power so am not concerned with it running down. I is just a pain to have to hit the power button every 30 minutes. Other car radios I have just put power to the ACC blue wire to turn on the radio but the MB radio it knows the key is off.

Any solutions out there would be helpful.
 

RVBarry

2023 AWD 170 DIY CamperVan
Radio On module for VS30:

 

SSTraveler

2014 LTV Unity Murphy Bed
Leisure direct wired my 2014 model radio to the house batteries with a switch, but this isn't possible on the 2019 and newer chassis models because the radio is integrated with the Mercedes CAN bus. Evidently, Mid City Engineering makes what is called the 907 RAD ON kit, which makes the CAN bus think it's on accessory mode, but really the key has been removed. It doesn't show up on their website you evidently have to call them to ask for this fairly new product. It is something like $375. Start reading from post#47, https://sprinter-source.com/forums/index.php?threads/82465/page-3#post-907070. Evidently the radio operation still draws from the chassis starter battery, so you would need a way to combine the house and Chassis batteries for times when you want to use the radio while camping so you don't drain the starter battery down. You could add something simple like a Trik-L-Start/Amp-L-Start on a switch so it doesn't interfere with your Sterling dc to dc charger as Treemaze did in this thread, https://sprinter-source.com/forums/index.php?threads/91040/. The Amp-L-Start is now Lithium battery compatible, so if installed with a switch, would provide a way to manually combine the house batteries with the chassis battery for chassis starter battery trickle charging when on shore/generator power or solar power. It would be a great addition for those who have AGM or Lithium house batteries and want to keep their chassis battery charged while parked or in storage.
 
Last edited:

Top Bottom