IF this thread does not belong into this section, I very much apologize and a mod please move it to the proper section. Thank You.


I have a job that involves house protection and surveillance for 8-12-13 hours continuously, all the time car parked in private driveways of multi-million-dollar mansions and stay in the car for the entire duration of the shift.
Always access to an outdoor power outlet where I always plug my extension cord for my own ceramic heater I use in the car. In Toronto, Canada winters are pretty harsh.
Running a brand-new Honda battery in excellent condition, I'm also running Beltronics STI radar detector and in pilot mode it shows me the battery voltage while driving and anytime after I turned the engine off. Driving: 14.8V, right after I turn the engine off: 13.2V.
Now comes the bad part.
I have SiriusXM sat radio, Stratus 6 radio, connected directly to the Accessory Power Socket, on the car radio display I have AUX.
For the 8-13 hour long shifts when car is parked all the time I have only the sat radio connected to the cigarette lighter plus ceiling light is off (after dark I'm using a very powerful flashlight), also regardless the weather outside, snow for instance, I do not use the windshield wipers, in other words no other source of car battery usage other than the sat radio itself.
After ~6 hours of continuously running the sat radio, battery voltage drops to only 12V and soon after bellow 12 V when you soon risk to drain the entire battery so you'll need a jump boost from another car.
All I want is not to turn on the engine for the entire duration of the 8-12-13 hour shift, burning gas and money of course, but still using the sat radio for the entire duration of the shift, w/o draining the battery bellow 12V.
I do not want to spend extra money on battery chargers or other large and expensive devices like a second battery kept by the passenger side and hardwired to the fuse box or something similar, therefore Q please: anything else I can do, anything more I can do, to be able to listen to sat radio for the entire duration of the long shifts with no engine running and still not draining the battery?
In the warm seasons, April to Nov, everything is fine, including running sat radio and cell phone charger for same very long hours with no engine running and battery voltage stays steady above 12V, therefore my issue is only for the winter season which will hopefully end in max two months.
Maybe somebody has got some more ideas.
Thank you very much and I apologize for the long post.
Chris in Toronto

 

I dont know if a block heater would help or perhaps taking the battery out and insulating it with thermal wrap or something.

 

Thank you Lance but a block heater is very good the keep the engine warm during very cold winters, mostly below -20C, and has got nothing to do with charging the battery plus for just max two more months of winter I'm not into spending money on stuff that will not be needed from April to Dec.


I know that my Fit Sport has got 6 speakers all controlled by the radio system and fader, F for Front, R for Rear and C of course, no idea IF using only the front speakers will reduce battery usage for the duration of my long shifts.


Unfortunately this model (or maybe all Fit models for that matter) does not allow to dim to zero the radio display brightness while parked and engine not running, only while driving with lights on.


All the best, Lance.

 

The OEM battery in the Fit has a small capacity. Most replacement batteries of the same physical size do also. I'm using an Optima Yellow Top. It is a very good battery, but still will discharge quickly in a scenario such as yours.

Since you already have AC coming into the car (for the heater), I suggest you just keep the car turned off completely and power your radios, etc from the AC source via a power supply or AC adapter.

 

Too bad you just bought a new Honda battery (I assume a 151R), For less money, you could have gotten a 51R. Much more reserve capacity for those long shifts.

 

Get your self a $25.00 1, 2, or 6 amp battery charger. The make some that are about 1/2 the size of a brick these days. Plug it into the accessory plug on your dash and the 110 volt side into the same plug where you have the heater. That should keep the battery alive a few hours longer. If you are running down the battery that much, and that often be prepared to be buying another new battery soon. These starting type batteries do not like to be run below about 45 or 50% very often.

Here is a 12 volt 6 amp computer supply that will do the same thing.

http://www.ebay.com/itm/DC12V-6A-72W-AC-Adapter-Power-Supply-Charger-Power-Cord-For-Laptop-LED-Strips-/131432991409?pt=LH_DefaultDomain_0&hash=item1e9a044ab1
Check Crappy Tire or Princess Auto and see what they have in cheap battery chargers. I do not know Toronto well enough to give you a better place to look for one. Maybe Wally World?


Here is a 4 amp one at US Wally World

Schumacher 4/2 Amp Charger/Maintainer - Walmart.com

There is no way of getting around it. If you take power out of the battery you are going to need to replace it with some kind of battery charger or power supply. .

 

Thank you for the reply, Craig.


Unfortunately my Stratus 6 sat radio same like all sat radios out there runs only on the 12V accessory power socket, no idea how to connect it to my extension cord that powers the ceramic heater in my parked car.


Plus, I listen to sat radio via Fit's radio system, therefore I'll also need to connect the entire radio system, speakers included, to the same AC power source.


I guess all I'm waiting for is the end of the damn winter and everything will work properly in warm weather.

 

The paid car battery went dead with 1-2 months before the final day of the full warranty so they gave me a FREE brand-new Honda battery, after they tested the bad battery for themselves.
They hate when they have to honor a full warranty and give you something for free.

 

Sorry I don't get it, how do I continuously charge the car battery located under the hood while car is parked using the in-car under the dashboard accessory plug and a device who connects that particular accessory plug to the AC extension cord used for my heater, I don't think this particular "trick" is ever possible.


A real battery charger continuously attached to the + and - of the battery is too big to allow you to fully close down the hood and for an eventual device that gets connected to the extension cord INSIDE the car you need to run another sort of cable or wire from inside the car to the car battery located under the hood, right?


The device you gave me the link for is for a laptop or any other electronics located INSIDE the car where the accessory plug and the eventual AC power outlet are located as well, right?


PS I've found this device on Princess Auto's website, one of their stores is close to my home off hwy 401 in East Toronto, no idea if it will properly do the job for me:


http://www.princessauto.com/en/detai...er/A-p8487332e

 

Let me see if I can explain better what you need and maybe you can answer some additional questions for me.

Here are my assumptions:

You have a satellite receiver that you want to run for an extended period of time and that receiver gets it's power from your 12 volt accessory / cigarette lighter type socket in the dash of your 2007 Honda Fit. This satellite radio then feeds the car radio either by RF (radio Frequency) or by some kind of cabling, maybe the USB, and you listen to the programs using your built in radio and speakers.

If the above is true, then you need to have power available to both the satellite receiver and the built in car radio. To do this you must have the ignition turned to the accessory position or on.

So now we need to determine how much power the above consumes and supply at least that much power so the battery does not run down over the many hours of use without the engine running. I looked at a 2009 Fit repair manual I have here and it appears that there is a 7.5 amp fuse in line for the audio unit. I can not tell what a 2007 Fit uses but I will assume that it is similar to the US 2009 Fit.

So based on the above I am assuming that the power consumption is never over 5 or 6 amps. I will also assume that the Satellite receiver is very low or about .5 amps.

Based on the above assumption you would need a power supply of at least 6 amps to keep up with that setup. 8 or 10 amps would be even better.

Now how do we get that amount of power. A battery charger would do it. Battery chargers take 120 volts AC and make it into 13.5 to 14.5 volts DC. The DC is not clean. It is a ripple or pulsing DC but automotive batteries do not care about the ripple. If other devices are turned on using some of the battery charger power, the battery usually filters out most of that ripple. This is no different than when your alternator is charging or powering your vehicle. This is why I suggested that you look at using a battery charger to supply your power needs.

Laptop computer power supplies also take in 120 or 240 volts AC and convert it to DC. EXCEPT they make very clean DC. So a computer supply in the 12 to 14 volt area will supply a radio and supply very clean DC without the need of a battery being on line to filter out the ripple. I have one in my hangar powering a old GM car radio that has been powered on continuously for over 10 years and supplying that radio. Yes, we turn the radio off but we never turn off the power supply.

To charge to the vehicle battery or supply power to the vehicle you do not need to attach your power supply / battery charger direct to the battery. You can connect the power supply to anything that is wired to that battery. This is why a connection to the accessory plug in your car is a good attachment solution. Many small battery chargers do it this way. The main problem with this approach is that Honda has chosen to turn off the accessory socket when the ignition switch is off. So charging the battery or supplying power to the rest of the vehicle will only work on a Hionda when the ignition switch is in the accessory or on position. I believe that you are already doing this when you are listening to the satellite radio so this Honda restriction does not appear to be a problem in your situation.

So If you were to supply 12.5 to 14.5 volts DC at the accessory plug and turn the ignition switch to the accessory position, The 12 volts would back feed to the rest of the vehicle and solve your power problem.

I briefly looked at the Schumacher supply you referenced on the Princess Auto site. It "appears" to come with a 12 volt accessory plug that could be used and will supply 4 or 6 amps. I tried to download the manual for it on the Princess Auto site and the site sent me to a dead URL. I tried to find the manual elsewhere on the net but the SKU number appears to a Princess Auto number only. I'll keep looking and hopefully I'll find it.

One other assumption I need you to verify. Does the Canadian 2007 GD Fit have only one accessory 12 volt socket?

 

If an actual measurement shows that the current draw is more than 0.040 to 0.050 amps (40-50ma) than your battery will be drained in short order at a rate of 0.50 amps (500ma!) My own 2008 Honda Fit Sport 5-speed shows a current draw of 15 to 17ma using a precision Fluke 8060A digital meter. The measured drain on our other vehicles (2003 VW Glof TDI, 2015 VW Golf TDI and 1983 BMW 528e) are all below 40ma or 0.040 amps.

I would take an accurate measurement of the current draw that your battery is being asked to deliver when off and parked.
-Rod

 

Good Point..You know what I forgot is he has the key on in the accessory position and that will prevent the computer(s) for going to sleep. So there is additional current draw there.

As was stated, rather than guessing, the best thing is to just measure what you are drawing and supply a little more than that with whatever power supply or battery charger you choose to use.

 

Additional info about parasitic battery drain current amounts -

While my own 2007-2008 Honda Fit Service Manual P/N 61SAA01 does not indicate what level of parasitic battery drain current is typical or acceptable, here are links to other comments about the problem of Honda batteries having problems maintaining a charge and what an 'acceptable' level of parasitic battery drain current is and how to check it, with reference to other electrical parts that need to have gone to sleep, first, before you take your measurements.

Parasitic Battery Drains - Diagnostic News

Testing for Battery Drain - Randy's Repair Shop

Battery Drain

-Rod

 

Those were two good articles Rod.

I did some extensive research on this matter while chasing a parasitic draw on a GM product a few years back. I found that the GM design requirement was all their vehicles had to drawn less the .020 (20 ma). Mine was running 350 ma. at the time. I finally got it down to 18 ma. So I now use that number (20ma) whenever I'm chasing a problem on any brand of vehicle.

The OP never came back. I wonder what the decided to do.

 

20ma may be a bit too tight, given what I have also seen on a number of other vehicles, especially fairly new ones, with lots of gizmos. I am using 30-35ma range and also insuring I am not doing this test too soon, as some vehicle systems enter sleep or off mode in 20 seconds, while I've seen others take the better part of 30 minutes! Ah what fun, eh?
-Rod

 

If I had one that was not down to 20 ma, but 30 or 35 instead, I also would not worry about it. You are correct, they keep adding more and more electronic stuff to the newer cars and I see how the parasitic drain could easily rise. The second thing the GM design point said was they wanted to be able to park a vehicle for 28 days and still be able to start it.

 

Rod and n9cv, thank you both for the very detailed replies to my original post.


Yesterday I had a damn long 12-hr shift, 08:00 to 20:00, ran the SiriusXM sat radio for at least 8 hours, NASCAR Radio ch 90 and Daytona 500, turned on the engine just once right before the end of the 12-hr shift and no problems whatsoever.
The only major difference, air temp was about 28F.
12.3V battery voltage when I turned on the engine before the end of the 12-hr shift.
Therefore the air temperature makes a huge difference when listening to the sat radio via car radio system and speakers while not running the engine.
Hopefully soon temps around or above 32F when my battery "problems" will be all gone for now until next winter of course.
Thank you all for your very helpful replies.
God Bless.