7 pin plug charging?

[NickM]

Anyone know which fuse protects the 12 volt source that goes to the charging pin on the 7 pin plug? My Precept 35S quit charging my Jeep Wrangler yesterday and the battery died in the afternoon, no power for my RVI2 brake. Towed the last 100 miles without brakes in the Jeep.

I looked under the dash, upper left side this morning and didn’t find any blown fuses. Next option is to look under the hood. I wouldn’t think Jayco or Ford would fuse that lead in the main breaker/fuse panel but will check there also this evening when we get back from Makinac Island.

[cfisher523]

Dumb question.... Did you check the fuse at the Wrangler's battery, if you have one? My charge line has a fuse in it just before it connects to the battery in my Traverse.

[Grumpy]

Originally Posted by NickM

I wouldn’t think Jayco or Ford would fuse that lead in the main breaker/fuse panel but will check there also this evening when we get back from Makinac Island.

All manufacturers fuse that line in the main fuse block normally.

[NickM]

The line I installed with fuse at the battery was the first place I checked.

Main fuse block? One under the dash, one in the engine compartment, one under the bed and who knows where else to find a fuse or breaker. I can find it by process of elimination but hoping to find someone who has already been down this path.

[theracqueteer]

it is normally fused in the fuse block under the hood.

[NickM]

Looked at fuses under the hood, nothing obviously blown that relates to towing. Called Jayco CS and tech said that 7 pin plug wiring was provided by Ford on the F53 chassis and their owners manual would have that fuse identified.

Looked at my owners manual and googled this subject and everything I found says Ford does not hook up the charging line, leaves it up to the body builder, in this case Jayco, who blew me off.

So, back to square one. When looking at the main fuse block under the hood I see several wires near the chassis battery that have in-line fuses. These are not identified in any owners manual I have so I’ll check them when I have more free time. I just love chasing my tail lik a dog.

[NickM]

Since I have not found a blown fuse I decided to troubleshoot the charging circuit from a different direction, at the 7 pin connector.

Measure 14.6 volts with engine running and 13.5 with the ignition off at the receptacle, nothing wrong here except the charging line is not switched, hot all the time.

Started on the wrangler 6 pin plug, had continuity from the charging pin to the battery and could measure battery voltage at the 6 pin connector. Nothing wrong here.

So now the problem of the blown fuse is eliminated but the new problem is why did my wrangler battery run down? We also experienced a similar issue during our 2 day travel, any time I shut off the coach engine the refrigerator would alarm and not switch to LP. Could not force it to LP with the mode switch.

The dinky battery level gauge on the generator panel would show empty during this period. How could that be? What is draining the house battery while driving because the alternator should be providing some level of charge.

I’ll be installing new house batteries on Monday but I don’t think that gives me a warm and fuzzy feeling that new batteries will solve the problem. I can’t see the wrangler as the culprit for draining the house batteries so something weird is going on with my 12 volt system.

Running the generator allows the fridge to run on LP and charge the house batteries. They show full after a few hours on shore power and I can manually switch the fridge to LP so no issues there.

I’ll be installing new house batteries on Monday and have a 2 day drive home next week to see what happens.

[Farris7]

I had the same issue- I ended up with installing a battery disconnect at the toad battery. Reason for this was that in order to unlock my toad steering I had to put the key in accessory, this caused the better to drain.

[NickM]

Maybe that’s better than charging the toad battery while traveling. Disconnecting my Jeep Wrangler battery will require resetting some info in the computer if I’m not mistaken.

I’ll be traveling back to Cincinnati tomorrow, will see how it goes with the new Duracell agm batteries.

[Tony p]

After also 3 months on the road i too lost the 12 volts at the 7-pin connector for my tow which is a 2020 Ranger, and my MH is a 34G 2022. Called Jayco they said it was a Ford problem, Ford said they only go 18 inches pass the gas tank and there a connector that Jayco would hook up for lights and 7 pin connectors. They both are no help> I checked the 30-amp fuse in the engine compartment is OK. There is a relay in the battery compartment that i have ordered thinking it could be bad will see. Is there any other fuses. Sorry NickM for making this so long and steeling your post

[Gary207]

Check out Blue Sea Systems Battery Link or ask them witch one of there products would solve your problem of not having to disconnect the toad battery

[Parrott]

I installed a drive/tow switch. Easy install. You just replace the accessory fuse with this wiring harness. I did install a lighter socket wired directly to the battery to run my irv brake system.