Jack,

In your new TV, when the original blew, did you install another 30 amp fuse?

Jim

Yes I did, Jim. I have no idea why the original 30 Amp fuse blew. It was on a two day trip to Rocky Mountain National Park and I think it blew on the 2nd day. The first night we stayed in a campground with shore power and I used that for the fridge, so it could have blown on the 1st day too.

I replaced the fuse in Estes Park, and it's been fine ever since. Five days on the road coming home - many stops at different "boondock" sites and then we've had the trailer on the road maybe 5-6 times after that, all to boondock sites and no problems whatsoever. No clue what broke the fuse the first time (but I have two spares now).

Someday I MAY run an additional fused wire to the trailer plug as has been suggested here.

- Jack

Jim,
Our Hi-Lo dealer told us it was perfectly safe to run our fridge on propane while traveling also. We also have a 2004. He said there was plenty of air movement inside the hi-lo and it also has a vent to vent it when in the towing postion. Our fridge is on the opposite side of trailer from gas pumps which he said wouldn't cause any problems either with using propane while towing. We have been running our fridge on propane since we first purchased it in 2004 while traveling down the road. Our friends that own a 2007 Hi-Lo were told the same thing by a completely different dealer he was also located in a different state. I guess it's up to each person how they want to run their fridge. We looked at alot of different travel trailers a few months ago and they're getting away from the DC option on fridges and only having the propane/electric option. So I don't know how these folks with new travel trailers are keeping their food cold while traveling if it's illegal to run on propane while traveling and the DC option is fading.

JackandJanet,
This may be the cause your fuse blew.
Shortly after we got our first Hi-LO, I had trouble with the fuse blowing, also. After blowing it many times, I found that if the trailer battery is down a little, when you put the top up the lift motor tries to draw power from the TV battery and will blow the fuse. The solution is to unplug the trailer before raising the top. I got tired of this and also kept forgetting to unplug- and kept blowing the fuse, my solution was to install a relay that disconnects the 12 volt line to the TV, it is activated when you push the up button. No more blown fuses.
I also installed a relay in the new trailer right after getting it.

Good thought, Pop! If the refrigerator was also running, there would have been a large draw on the 12-V line. And, I think this happened before I decided to install a second battery in parallel in the trailer. That second battery has seemed to make quite a difference in the state of the trailer battery charge after a day of towing.

- Jack

I always run the refrigerator on 12 volts and the fan while towing and if you blow the fuse and don't know it, you wind up with a totally dead trailer battery after several hours of towing. The 95T only had one battery and no room for a second, I have 2 in the 2209T but I installed the 12 volt auto relay any way as I didn't want 2 dead batteries.
My refrigerator stays under 40 degrees in the food section even in 90 degree weather while towing on 12 volts DC.
:D I must have a special refrigerator.:)

Hey Pop!
Good info! Can you please let me know schematically how to connect this relay, where you located it and the part number, mfr, etc. of the relay you used? This sounds like a really good fix to put into my 2207T.

Thanks,
Jeff

Jeff,

We had a similar problem years back when using a 1991 Ford F-150 as a TV. I went to an auto-electrical specialist and they recommended installing a "battery isolator." This was a solid state device about 2 X 4 X 5 inches that I installed on a side wall under the hood. Do-it-yourself install and forget. No switches and no more blown fuses. Most RV dealers carry them and price varies according to capacity.

Jim

I don't like the battery isolators as there is a voltage drop going thru them and getting enough voltage to the Hi-Lo refrigerator is a problem to start with. Some are better than others, the drop thru the diode is several tenths of a volt. The problem is that the trailer battery is several feet away from the TV battery. In a motor home the batteries are close to each other, and the wire is heavy gauge. When your dealing with low voltage like a 12 volt system small losses can be a problem. Ok, that was my reason for not using an isolator.
An isolator should work ok if the TV wiring is a heavy enough gauge. You should check the voltage at the trailer battery with the TV running, it has to be at least 13 volts to keep the trailer batteries charged and if you run the fridge on DC while driving, it should be turned on also before doing the voltage check at the trailer battery. If the voltage at the trailer battery is less than 13 and you run the fridge on DC you may wind up with a dead or low trailer battery. The closer the voltage at the trailer battery is to the voltage at the TV battery, (which will be from 13 to over 14 volts), with the TV running, the better everything will work.
Try the Isolator it comes with a schematic and is easy to wire in.

I used two12 volt 30 Amp Auto relays that I got at the local salvage yard, couple bucks, I wired them in parallel, creating a 60 amp relay, breaking the 12 volt plus line in the trailer battery box. The coils are wired to the pump relay in the battery box. I tend to do everything a little on the over kill side, but once done it's done and reliable. I can draw you a schematic but because I used 2 relays it gets rather complicated. I don't know of a single auto relay the would be over 30 amps and with the TV fused at 30 Amps the relay has to be greater or it will burn out.

Hi Pop,

Didn't know that about the voltage drop through the diode, but I just followed the installation directions and ran the recommended 10 gauge wire back to the trailer. Also, with that trailer I couldn't run the refrigerator while underway... so all TV power through the isolator went to charging the trailer battery only.

I will say that with the installation of the battery isolator, for the first time in all the years of towing that trailer, I finally eliminated all the problems I'd been having with blown fuses, a chronically run down trailer battery, etc. That solution worked worked well for that application. :)

Jim

Using the battery isolater?

I am not sure I understand what or how you accomplished no more fuse blowing! unless you wired everything differently than we did in motorhomes...

A Battery isolator, at least the ones I been around, should only essentially remove the T.V.'s battery from (plugin at the bumper I guess is the easy way to describe it) until the engine is running. once the engine shuts off, the T.V. battery would unhook (so to speak) & there would be no power on the lead at the connector's wire at the bumper (of course also at the same wire under the hood). But, when engine is running it would allow battery to charge as well as share that charging voltage to the battery in the camper.

BUT, you should still blow fuses once you started the engine, if the battery in the camper (or whatever you hooked to the plugin) draws more than 30 amps... :confused: So my thought is that the better wire to the connector probably fixed the fuse blowing?

Hi Sting,

Well, I've never claimed to be an electronics tech... so I tend to go by what "those in the know," tell me when it comes to that realm. Unfortunately, neither do I have a photographic memory. So the exact reasoning and explanation given to me at that time (late 1991) escapes me, but I do remember it making sense... didn't have a wonderful HTF to turn to with these questions! :)

The trailer battery was frequently discharged (no doubt because it wasn't being charged due to the blown fuse) and probably blowing replacement fuses because of the current surge when I plugged into the TV. For years I gave up on charging the trailer battery while underway. I'd get 5 to 10 top raisings out of the battery and would then put the trickle charger (we always carried) on it and charge it up. So you're probably correct about the heavier wire connecting the TV battery and trailer battery. I always thought the isolator had more to do with. Guess I was fed some bad info... my apologies if I've mislead any readers.:(

Bottom line... whatever fixed it, I was happy!

Jim

Please Jim, we're all about discussions on here! I was NOT condeming nor complaining about information in your post as much as I was wondering... I didnt mean to sound like "couldnt be" I only meant normally probably wouldnt be. I have to admit, I learn new things everyday. I forget about 3 though, everyday, I think.

Accept my apologies. I just thought I would ASK, though maybe it didn't sound like it to you reading it, as did in my head when I typed it...

It sounded like (use your best Star Trek's Mr. Spock voice) "interesting" (voice off).

I know exactly how the memory thing works, I was asked about what we did last year to fix an issue on a JohnDeere Combine (used in agriculture for harvesting many crops, for those also viewing this thread and never seen one) and I'll be damned if I can't only recall a couple facts, and one "I think it was..." :p

I conceed, that there is a chance, with the right help, they might have had a trick setup and instructions for you (when you had troubles maybe) and had you try to do things a different way... Ive seen a lot, but I won't say I have seen it all...

Cheers all, Sting32

Sting
a battery Isolator will work but again it has to be wired in correctly. The whole idea behind preventing the TV fuse from blowing when the top is raised, is to stop the lift motor from drawing power from the TV. The lift motor draws at least 75 amps as it is a converted starter motor. In the old Hi-Lo s it was a prestolite starter motor, an the manual said you could get one at an auto parts for replacement.
Check the first diagram in this PDF, battery #2 would be the trailer battery, the circuit breaker would be the fuse in the TV and the 2 batteries would be isolated from each other, neither could draw power from the other.

Sting,
Its cool. The HTF is also about honesty and giving good and valid information, which is why I responded the way I did. I realized I didn't know enough about battery isolators to recommend them.

Pop,
Thanks for the facts about isolators. In fact our 1969 does have a pure starter motor operating the hydraulic pump, and I've always been pretty lax about unplugging the trailer when making a simple overnight stop. So raising the top could also have been a source of blown fuses.

In any event, either by installing the isolator, or a heavier gauge charging wire, the problem was fixed.

Thanks, Jim

Jim,
The Isolator stopped the fuse from blowing not the heavier gauge wire.
I can't understand why Hi-Lo never addressed this problem. I guess if someone complained of the TV fuse blowing, they left it up to the dealer to fix.
Richard

Just throwing in a side note: If you test your breakaway emergency brake switch, be sure to unplug from you tow vehicle or you may blow out your break controller. That may not be true for all controllers, but why chance it.

Question. If that may happen when you are testing it, what happens when you actually need it?

I think when you actually need it, the brake controller will be the least of your concerns. You will have far more serious things happening.

Jack and Richie's diagnosis was correct...the 30 amp charging fuse was blown in the TV. I inaccurately described the battery condition as DEAD....when, in fact, it was extremely low to the point when I attempted to raise the top...it had enough juice to bring it up about 3 inches....then died.

At any rate, I believe what happened is this...since the 12 volt charging fuse blew in the TV, the battery was not being charged at all during the trip therefore accounting for the low charge state of the battery. The fridge ran the entire trip on DC using the HiLo battery, of course...so, it was plenty cold when we got to our destination.

Here is the problem now...there are apparently two tow fuses on a 2005 Nissan Xterra...one is a 15 amp blade fuse (runs the lights?) and the other is a 30 amp wire fuse with 2 other fuses contained in a rectangle box housing inside the TV fuse box under the hood. I am not sure how to replace this one. I can't tell if it is screwed in...or snapped in...or if I pull the whole box out that contains all three wire looking fuses.

Anyone ever see this type of fuse (and know how to get it out to replace) ?