Radio Switch Drains Batteries?

[BroncoHauler]

Originally Posted by oldbonesclimber

After thinking more about it, the easiest way to determine if it is 100% true, which I believe it is, is to switch to Van Battery and UNPLUG the Radio fuse in the House fuse panel. If you can put the ignition key on ACC and play the radio it is not wired this way. This is because you should be running on the Van Battery. I'm chicken as it may lose all the Stereo presets and security codes. I would feel honored if someone would be brave enough to test this.


Paul

Sure, I'll be happy to pull the radio fuse, in your van.


Herb

[jage]

I determined radio fuse and correct function by switching to ON (Radio Extra Battery, switch light on) and turning the radio on.

The fourth fuse from the top (or 1st in the second group of 3) disabled the radio. Thus step 1:

Radio Fuse Out
1. With switch ON
- no radio (power button does nothing)
- no light on switch
- pressing clk button brings up clock and cd motor (normal for key off)

2. With switch ON and Key in ACC position
- no radio
- no light on switch
- pressing clk button brings up clock and cd motor

3. With switch OFF
- no radio
- no light on switch
- pressing clk button brings up clock...

4. With switch OFF and Key in ACC position
- RADIO!
- LIGHT on switch

Normal operation (fuse in place):
5. With switch ON regardless of Key in ACC or not
- RADIO!
- LIGHT on switch

6. With switch OFF and Key in ACC
- RADIO!
- LIGHT on switch

7. With switch OFF and Key OFF
- no radio
- no light on switch
- pressing clk button brings up clock...

[jage]

Since I don't hear a relay (and having not looked at the wiring) this is my guess as to how my van is wired. This matches the way SMB handled the reverse lights override.

I agree that this is not the only way to wire a van, and I wouldn't be surprised if they are wired in many different ways.

Again, this is based on the above only, not actually looking at the wiring:

(Apologies for the poor diagram, I'm trying to use GIMP and it's very difficult coming from Windoze platform graphics)

[daveb]

Might depend on what type of radio you have and who wired it. Your pic Jage does not fit my application.
I can only run my radio if #1-the vehicle is running, or #2-the key is in Acc, or #3-the SMB radio switch is in the "on" position. One problem I had was when the SMB radio switch was "on", it also fired up the subwoffer amp which caused a super large draw on my house battery. So Randy(SMB) added a dash switch up front so I can dissable it at any time in any mode. But I also have an amp for the radio itself and there was no way to interrupt power to it (W/O stopping the sound stream), so when the radio is on, that particular amp draws a good amount of current from the house battery when powered by the SMB switch in the "on" position. I live with it because I have twin house batteries and don't worry too much about overnite. (I can dissable that amp by actually turning off the amp via the bypass switch on the amp). But if I leave everything on with the music blaring and the SMB switch "ON", my gauges read a hefty draw off the house batteries.
At least that's how mine works So far I've never found that the sound system has affected the chassis battery system while the SMB radio switch is in the ON position

[dowgars]

Help: I can't follow all this, however I'll try the forum before I call SMB monday.
My van is a 2009 V-10. The radio plays only when the switch is on Acc, or On, and for about 10 minutes after I pull the key out. (unless I open a door.) The Radio Master seems to do nothing (It might be causing most power for the radio to be pulling from the large house battery.)
Therefore No Key = No Radio. Is that correct? I would think I could run my radio directly from the house battery???
Thanks for any answers. RD

[jage]

Sounds like you're incorrectly wired to the vanity wire as I call it. It drove me crazy because it would be on one minute and off the next with no key, or on again with key, but then on with key-off.

My radio also stays on after driving until I open a door. I've never left it on long enough to see if 10 minutes is the limit, but if you open the door and it immediately goes off, that's what I have.

[dowgars]

Yes-mine goes off the minute I open the door. I just had thought I could use the radio without the key in the ignition.

[daveb]

Originally Posted by dowgars

Yes-mine goes off the minute I open the door. I just had thought I could use the radio without the key in the ignition.

The radio switch is a bypass to keep you from having to use the accessory ignition on. Jage is right about the 10 min or so. This is typical of most newer vehicles and even the windows will operate in some cases. As long as a door is not opened, the radio will continue to play. If I turn off the radio switch before the Ford system (10 min) times out, the radio will stay on until I open the door.

The door opening shuts down the Ford system at any time. If I climb in back and turn on the radio switch, I can sit and listen to the stereo until bed time off the house batteries. But one of my amps runs from the house power source while the other runs off the chassis system. My build.

Crystal Clear?

[dowgars]

I believe mine acted like that when I picked up the van over a year ago but now the master (that say's on it "Extra battery switch") does nothing. The radio still goes off in 10 minutes after pulling the key. It's like the switch is not in the system. ??????

[daveb]

Not sure but it might be a relay controlled circuit. A call to SMB might clear up where to look. Maybe a wire off or open fuse.