Enabling TV while driving

Hi there,

We have a 2015 Coachman Leprechaun that has a TV mounted above the top sleeper, so not where the driver can watch it. We want our two young daughters to be able to watch DVDs on the TV while we're driving long distances. I know you need the generator on, but it still isn't working. I know it's a safety feature. The salesperson told us he wasn't allowed to tell us how to bypass this (obviously) but that it could be done.

Anyone able to share?

I swear no one up front is watching!!! TIA

I would consider buying a portable DVD player.  They're inexpensive compared to a few year ago and have the advantage of not having to run the generator and using up additional gas.  That is unless you are also running the generator to cool the main cabin.  Another advantage is that the girls can use head phones or ear buds to listen to the player rather than turn the volume on the TV up loud enough to be heard over the road noise  which can be annoying to those in the cab.  Get 2 and each girl can watch what they want, avoiding arguments, which can also be annoying those in the cab.  Happy RVing everyone.

The tv power cord is plugged into an outlet that is deactivated when the engine ignition switch is on. If there is another outlet nearby, use that instead.  Or an extension cord from somewhere else.  Alternative: The outlet has a gadget built in that deactivates it when 12v power from the ignition is present. Remove the 12v wire from the back of the outlet and it won't shut off anymore.

Here's another alternative.
My 32" TV and antenna amp run fine off a 75 watt inverter powered by 12 volts. No need to run your generator.

Tom

Heli_av8tor said:

Here's another alternative.
My 32" TV and antenna amp run fine off a 75 watt inverter powered by 12 volts. No need to run your generator.

Tom

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Exactly!  I have a 100w inverter that is plugged into a DC line.  Runs the TV fine with or without power. When we get to shore power we just plug it in where it belongs.

satxron said:

Exactly!  I have a 100w inverter that is plugged into a DC line.  Runs the TV fine with or without power. When we get to shore power we just plug it in where it belongs.

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I used to do this when we fulltimed in our 5th wheel. I used an inverter to power my cpap when we would overnight at rest stops, truck stops, etc. there was an auxiliary DC outlet (cigarette lighter type) in the bedroom. Worked great.

Inverter plus another tv (or the same one) is a fine alternative. However, I chuckle at the concern many have for running the genset and using fuel. Why have it if you aren't gonna use it? Fuel consumption for a measly 100 watts of power is trivial, maybe 0.2-0.25 gal/hour, so a gallon or so entertains the kids for a travel day. And do you think the inverter is free? Watts are watts, and have to come from somewhere. If you are drawing the watts from the vehicle as you drive, that uses engine horsepower to produce them (the house batteries get engine alternator charging too).  There is no free lunch.

also if you run the generator turn on the AC and "exercise" it - good for the generator

On many RVs there is indeed an Ignition Interlock on the TV.. Mine included.

I've seen a lot of "Cut this or do that" posts. but here is the absolutly EASIEST way to defeat the interlock,

Plug the TV into a different outlet.. Does not void warranty, Requires NO changes in anything that might some day need to be "Fixed".. Just move the plug. Job done,

Gary RV_Wizard said:

Inverter plus another tv (or the same one) is a fine alternative. However, I chuckle at the concern many have for running the genset and using fuel. Why have it if you aren't gonna use it? Fuel consumption for a measly 100 watts of power is trivial, maybe 0.2-0.25 gal/hour, so a gallon or so entertains the kids for a travel day. And do you think the inverter is free? Watts are watts, and have to come from somewhere. If you are drawing the watts from the vehicle as you drive, that uses engine horsepower to produce them (the house batteries get engine alternator charging too).  There is no free lunch.

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The vast majority of that fuel consumption is just the overhead needed to spin the generator.  I defy you to measure any difference in fuel consumption between an unloaded gen set and one powering a 100 watt load.

100 watts is 0.135 horsepower.

Again, you'll never be able to measure any difference in the main engine fuel consumption whether or not it's alternator is powering the TV.  In other words, for all practical matters  there IS a free lunch using the main engine alternator to run the TV.

But if you run the generator, the fuel consumption will increase by a measurable amount.  Using round numbers, a motor home that's getting 10 MPG and travelling 50 MPH will use 5 gallons of fuel per hour.  Increase that fuel consumption by 0.25 gph running the generator and the effective MPG will decrease by 0.5 MPG, from 10 MPG to 9.5 MPG.

Gary RV_Wizard said:

Inverter plus another tv (or the same one) is a fine alternative. However, I chuckle at the concern many have for running the genset and using fuel. Why have it if you aren't gonna use it? Fuel consumption for a measly 100 watts of power is trivial, maybe 0.2-0.25 gal/hour, so a gallon or so entertains the kids for a travel day. And do you think the inverter is free? Watts are watts, and have to come from somewhere. If you are drawing the watts from the vehicle as you drive, that uses engine horsepower to produce them (the house batteries get engine alternator charging too).  There is no free lunch.

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Excellent point Gary! Power is power and there is no reason to believe that a generator is less efficient than the engine, but I must confess I have been guilty of thinking that I ought not run the generator when I was traveling if I could avoid it.  Of course, if I am using this to cool the entire RV that probably is consuming more fuel, don't you think?

The vast majority of that fuel consumption is just the overhead needed to spin the generator.  I defy you to measure any difference in fuel consumption between an unloaded gen set and one powering a 100 watt load.

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I couldn't agree more! But there is a measurable difference between no/light load and 50% or 75% load, so running the a/c is measurably different than that 100W tv.  Onan clearly documents fuel consumption vs load in their manuals and brochures.
That's also why inverter gensets are often more fuel efficient overall. Their ability to reduce rpms for light loads lowers the minimum fuel consumption threshold vs a fixed rpm genset.

OK, ya got me.  :-[  For the light loads we are [mostly] talking about, the change in engine load is unmeasurable.  That's not to say that other, larger power consumers (e.g.  the dash a/c) have no effect, but this one is trivial.

JoelP said:

Excellent point Gary! Power is power and there is no reason to believe that a generator is less efficient than the engine, but I must confess I have been guilty of thinking that I ought not run the generator when I was traveling if I could avoid it.  Of course, if I am using this to cool the entire RV that probably is consuming more fuel, don't you think?

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Exactly.. When my Dash Air was out I burned a lot of fuel in the Onan, doing so just now as I'm on an anemic 20 amp site (I can not even make a cup of coffee without firing up ye old Onan)

But normally if I were driving the house electronics (computers, chargers, TV's DVR's) eat off an inverter, it eats off the main engin ealternator

Now. Effiency. The inverter is 90% and the alternator around 80- 85 (not sure has not improved much since Thomas Edison peaked it back in Menlo Park).

The Generator.. Same as the alternator.. HOWEVER not having the additional engine overhead more than makes up for the inverter loss,, WAY MORE.    Unless of course the dash A/C is either not working (Up till 2 weeks ago Monday) or overwhelmed (Common when driving across say AZ any time of year) and you need the addional 30,000 BTU's of COOL!!!

Of course, if I am using this to cool the entire RV that probably is consuming more fuel, don't you think?

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Probably. We rarely tried to cool the rear of the coach while driving, but had the front a/c on most days when it was much above 83 outside and sunny.  Our coach had a fair amount of black paint and sun loading was a problem, so the dash air was adequate only on cloudy days. Did not use the house a/c anywhere near as much with the previous mostly white coach.  Another "your mileage may vary".

Our Onan QD 7500 consumed 0.5 gal/hr at 50% load, which means 3750 watts in this case. Far more than two a/c in use. Running just the front air (about 1200 watts) was about no more than 0.25 gal/hr, so hardly noticeable for the 4-5 hours of our typical driving day.