Radio cutoff switch

[Audisteve]

Hi everybody, this is my first post on the forum. I have just bought an IH Savannah Tio R based on a Ducato 2.8 JTD, 54 reg to replace my VW T4. When I purchased the IH it had a CD player which would also play DVD's. The previous owner explained to me that there was always some power going to the player even after you turned off the ignition, hence the player was linked to a little switch on the dash which you had to turn off to isolate the player totally. I was not happy with performance of this player so decided to swap it for a Sony CDX-GT 414u with USB and AUX inputs. I installed the Sony but at first it would not hold the station memory so did the usual swapping of the red and yellow wires which solved the problem. It only comes on with the ignitiion turned on and I think I would prefer it to come on with the key at the first click (ACC position). Does anybody know how I can achieve this? Also, do I need the switch connected because it isn't at the moment and I can't remember which wires it was linked into on the old player. When I turn the player off there are no lights left on, no faint glow that I can see. I know I should have made a note of the old connections but I was more interested in getting a decent player in. Thanking you all in anticipation, Steve. :-S (?)

[StuartO]

Welcome to the Forum.

 

Modern car radios are often designed to empower their display lighting automatically when the ignition switch comes on, then you use the front panel switch to turn the radio itself on when you want it. Most MHs power the radio from the leisure battery so the radio can be used while stationary without draining the starter battery, so the power supply to both red and yellow cables is from the leisure battery.

 

Many modern car radios do not allow you to switch off completely at the front panel because they rely on the car's ignition switch to control the panel lighting, so if you fit one of those and connect both red and yellow to the leisure battery the display lighting of the radio would always be on, which you probably wouldn't want.

 

I bought a Sony as a replacement recently because its front panel switch does allow everything to be switched off (by holding the switch down for a while) so that when connected to the leisure battery I retain control from the front panel, separately from the vehicle ignition switch. It sounds like the previous owner of your MH solved a similar problem by introducing an extra switch to alow him to power off the radio completely.

 

If your Sony works like mine I would suggest connecting both red and yellow to the leisure battery to power the radio rather than continuing t use the ignition switch. If necessary run an extra cable from your habitation fuse board for the purpose or run a cable directly to the leisure battery via an in line fuse of no higher than 3 amp rating.

[Derek Uzzell]

StuartO - 2014-11-03 8:54 AM

 

...Most MHs power the radio from the leisure battery so the radio can be used while stationary without draining the starter battery, so the power supply to both red and yellow cables is from the leisure battery...

 

 

I would agree that it’s no bad idea to power a motorhome’s in-cab radio from the motorhome’s leisure-battery. However, I would have thought few motorhome manufacturers alter the base-vehicle’s standard specification (ie. a radio powered by the starter-battery) when converting that vehicle into a motorcaravan. If your motorhome (whatever make it is) has a leisure-battery-powered radio as standard, it’s likely to be unusual in that respect.

[spartan3956]

It is about time the builders wired the radio`s to the leisure batteries or at least programme the vehicle power circuit to last longer than 20 minutes

 

 

Pete

[Audisteve]

Thanks for your replies, but the first main point I was trying to make was that I would like the radio power to come on at the first click of the ignition key (ACC) before it gets to the point where all the ignition dash lights come on. Like I say, I can't see any lights or glow at all once the radio is turned off. Whichever battery the radio is wired up to worked fine for the old radio so I don't see the point in messing about with the supply. If I'm on a site and want the radio on I tend to turn the tv on and tune to a radio channel. As I also mentioned, do you think that I can just leave the two wires from the cutoff switch disconnected and taped up? Maybe I didn't explain very well in the original post, hope this clears it up about the Acc point turning on power. Thanks again, Steve.

[Billggski]

The yellow is usually a permanent live to retain the code and station presets, it should take a minimal current.

The red, as outlined, works on the ignition circuit, and in the x250 set up has a timer to protect the starter battery. I can see the point of putting a switch on this red wire, to replace the ignition switch if you wire it through the leisure battery.

[Derek Uzzell]

Steve’s motorhome will be based on an X244 Ducato, but that also had a 20-minute radio cut-off.

 

There’s a longish discussion about X244 radios here

 

http://www.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Fiat-radio-linked-to-ignition/4779/

 

though I’m a mite doubtful how applicable it will be to Steve’s question.

 

I understand what he wants to do (and it’s a perfectly reasonable wish) and that he wants to do it with minimal disruption to the vehicle’s present wiring, but I’m not sure if that will be practicable.

 

If I were fitting an 'after-market’ radio and was keen to have it work when the Ducato’s ignition-key was turned to the ACC position, I’d begin by checking what functioned when the the ACC position was selected and use that as a basis for providing power to the radio. However, this would quite likely involve adding a relay and supplementary wiring.

 

Regarding the cut-off switch fitted by the previous owner but now disconnected, as long as Steve’s Sony CDX-GT unit works OK and there’s no indication that the unit is using power when switched off, I’m tempted to think the cut-off switch is now redundant and can happoily be left disconnected with its end-wires taped up.

 

If there’s real concern that the Sony unit might be drawing power even when switched off, it would be sensible to check this by testing for current-drain at the battery.

 

[Audisteve]

Derek, thanks again for the reply. I am not sure if the switch on the dash was fitted by a previous owner or fitted by IH Motorhomes themselves. The MH is indeed based on an X244 (2.8JTD 54 reg). If anybody else on the forums has a similiar age of IH MH maybe they could tell me if their van has this switch. Failing that, I will probably take your advice and check if there is any power drain when all systems are turned off. Can anybody tell me the easiest way to do this? I might be worrying about nothing if the radio turns off totally like it appears to do, just want to make sure. Steve.

[Derek Uzzell]

If you GOOGLE-search on “vehicle check battery drain” you’ll find some stuff that should be helpful.

 

You’d need to take an amperage reading at (presumably) the starter-battery with your Sony unit connected (but switched off) and another reading with the unit completely disconnected. If the reading is higher in the former case, then the unit is draining power even when it is switched off.

 

Although it’s suggested on this youtube clip

that you may be able to make the check without losing certain stored data (eg. radio stations or a radio security code), you’d be better to assume that such data will be lost and will need to be re-input. I suspect that this won’t be an issue in your case, but it needs saying.