On switch

[Brad!]

Need some opinions with the following.

I currently have a Pioneer head unit in the car - Love the unit but it takes a good 30secs to load.

This is fine for normal driving but on weekends i use my car for the glamorous job of Pizza delivering. The 30 seconds becomes a pain in the ***** because i only leave my car for under 5mins but have to wait each time for it to load.

My thinking is what if i could put a switch in to leave the unit on for these short spurts of time...?

Run a wire from the main + to a switch - Run a wire from the switch to the acc power. Before i switch the car off i flick the switch which provides constant power - Car turns off unit stays on. When i get back in the car, start the car and flick the switch off.

Questions

1. Would it work

2. Is there a better way of doing it

3. Could it cause any problems.

Cheers

[chicken]

maybe you can use a delay off relay so it stays on for a period of time. but i don't think there is relay with a 5min delay...

[Guest]

maybe you can use a delay off relay so it stays on for a period of time. but i don't think there is relay with a 5min delay...

you could run a constant +12v line from somewhere to a switch, to the acc line of your h/u... flick the switch and kill the ignition.. but this would keep everything connected to your acc powered up.

[Brad!]

maybe you can use a delay off relay so it stays on for a period of time. but i don't think there is relay with a 5min delay...

you could run a constant +12v line from somewhere to a switch, to the acc line of your h/u... flick the switch and kill the ignition.. but this would keep everything connected to your acc powered up.

Besides draining the battery are there any issues with this?

[Guest]

maybe you can use a delay off relay so it stays on for a period of time. but i don't think there is relay with a 5min delay...

you could run a constant +12v line from somewhere to a switch, to the acc line of your h/u... flick the switch and kill the ignition.. but this would keep everything connected to your acc powered up.

Besides draining the battery are there any issues with this?

not that i can think of... would just be like leaving your keys in and on ACC.... just make sure you use big enough wire/switch/fuses

and maybe connect it straight to the acc part of the key barrel...

[thegourou20]

Is it because you try to read mp3 cds or is it with everything? :-l

[DJKOR]

No one thought of the obvious here.

Notice when you start your car, lights tend to dim and maybe even your head unit cuts out? This is because the power draw for the starter motor is quite high and your accessories usually lose their power.

One way to test if you should even bother with this is to turn your key to ACC, let your stereo load, then once it is running turn your car to ON then start it. See if your radio ends up resetting and going through the entire 30 second load again. If it does, then the switch idea is pointless. If it doesn't, then go ahead with it.

[Kiz_]

Probably not a good idea to run the power straight through the switch anyway. Use a relay. The switch will then draw a tiny current when on to activate the relay. Run a decent gauge wire from the batt, with an inline fuse, to the relay and then splice it into the head unit's ACC wire. This way your stereo will turn on and off with the car as normal AND on with the switch when the car is off.

What DJKOR said is correct, starting the engine may draw too much power through the system and cause the stereo to reset - I know mine does. This effect might not happen if you run your power direct from the battery but again if the battery voltage drops below the threshold of the head unit during cranking then your only other option is to use a massive capacitor or a 2nd battery... Is it really worth it?

Edited October 21, 2009 by Kieren

[Brad!]

Is it because you try to read mp3 cds or is it with everything? :-l

No its because its a Pioneer Nav system running windows CE and takes ages to boot

No one thought of the obvious here.

Notice when you start your car, lights tend to dim and maybe even your head unit cuts out? This is because the power draw for the starter motor is quite high and your accessories usually lose their power.

One way to test if you should even bother with this is to turn your key to ACC, let your stereo load, then once it is running turn your car to ON then start it. See if your radio ends up resetting and going through the entire 30 second load again. If it does, then the switch idea is pointless. If it doesn't, then go ahead with it.

I get what your saying but if im running the wire from the + power on the head unit to the Acc power on the head unit the unit would never turn off - Correct me if im wrong but isnt the ACC on the head unit similar to the Remote on your amp?

Thanks for the help guys - its a 2min job to run a wire from + to the acc to see if stays constant but i would rather get some input first!!

keep the replies coming!!

[Guest]

both daryl and kieran are right.... first thing to check is that if you turn the car to acc, let your HU boot up, and then turn the car ON and see it has to reboot or not... if it does not have to reboot then you are good to go.

next step, get a appropriately rated relay and a switch, use the relay to actually switch the current and the switch to activate the relay

[DJKOR]

Probably not a good idea to run the power straight through the switch anyway. Use a relay. The switch will then draw a tiny current when on to activate the relay. Run a decent gauge wire from the batt, with an inline fuse, to the relay and then splice it into the head unit's ACC wire. This way your stereo will turn on and off with the car as normal AND on with the switch when the car is off.

next step, get a appropriately rated relay and a switch, use the relay to actually switch the current and the switch to activate the relay

Yes a relay solution is the ideal solution...

But for Brad's specification, this is not entirely necessary. Just adding contribution due to the facts. I would still use a relay, but this idea stemed from a cost efficiency point of view... damn work budgets

If Brad is only turning the switch 'ON' while the car is running so that it will hold it's power, and then this switch will be remaining ON until the car is started again (I would assume it would otherwise the idea is invalid), then a simple switch is all that is needed. Because it only gets used once the head unit is running, there is going to be no sudden current draw that can create any arcing within the switch. Because the current is already flowing through the existing circuit, the switch only has a low current going through it at the time it changes state.

[Brad!]

You got it in One.

1. Drive car as normal

2. Flick switch to "ON"

3. Turn ignition off - Head unit remains on as normal

4. Get in car - Turn car on.

5. Flick switch to "OFF"

I guess i could test it by leaving the car switched off - Battery disconected - run wire from +12V on head unit to +ACC on head unit - Reconect battery, HU should now be on. Start car as normal - If the unit doesnt reboot then am i save to rig it up properly with relay and switch?

[httttt]

Just leave the keys in the car....... LOL. And run the risk of people distracting you at the front door while they sneak into your car and steal other peoples pizzas.

[STYLSH]

I have a bypass switch on my stereo. Just find a toggle switch and connect the headunit to it and constant power somewhere. I did it so that I dont need to leave the keys in the ignition at shows . Just find a spare spot in the fuse box and run a wire from there with a fuse.

Edited October 23, 2009 by STYLSH