Its a 2006 E350 Sportsmobile conversion, I've had it for about 8 years. It's had some odd electrical issues, one time I was camping in Montana a few weeks without any issues, the morning I started back to Colorado I drove about 60 miles and stoped to fuel up and get coffee. Got back in the van and the batteries were dead, not even enough juice to turn the engine. Had it towed to a Ford Dealer where it sat for a week before they could check it out. They could find no problems at all, they charged the batteries and it never happened again.

The latest issue is another oddity, I drove it to town yesterday and this morning I noticed the brake lights were on. It has hand controls so my first thought was somehow the hand control is slightly pushing on the brake pedal. I checked it visually and it looked OK, I then pulled up on the handle and there was no movement, I then checked the lights, they were still on. I then thought I should check the front parking lights, went to the front and closed the driver door on the way to the front, the parking lights weren't on. Went to check the brake lights again and they were off. They must have gone off when I closed the driver door. If the lights had been on all night I would expect the batteries to be low but it started fine as if the batteries were fully charged. There's no way anyone could have been messing around on it, I live in the country and my place is fully fenced in, and I have a dog.

What in the world could cause such an anomaly?

 

I suggest you start simple. If the brake lights are inappropriately on, chase that first.

At the same time, you need to be able to watch system voltage while the car is running. If you have a weak alternator and brake lights on all the time, that could be enough to allow a battery to go flat while driving. I suggest getting one of those cigarette-lighter voltage meter things that they sell everywhere as the easiest, fastest, and least-expensive way to do this. A step better would be to install an actual voltage gauge, but that'd be more permanent, and personally I wouldn't do that in this situation. With the cigarette-lighter unit, you can occasionally reference what it is up to. You can also watch it while getting gas etc. to see if it sits at 12.x or if it drifts down.

 

Thanks, I appreciate the advice

 

Where is it at today, still a problem or resolved itself? Seems like you have a grounding problem. They can be tricky to find, like looking for Waldo, lol. The place to start would be with the fuse panel. if it happens, then pull out a fuse, perhaps start with the brake fuse. If you pull it and the light goes out it might be on that circuit, but it might not be. Then put it back in and start pulling other fuses, best to start with one that are on all the time, like door light, or headlights. Pull one and see if the brake light goes out. If you pull say the door light or head light one and the brake light goes out, you probably have a bad ground on that circuit. They to find it becomes an interesting seek and destroy thing. Depending on where you live, how much you drive, etc will guide what shape the truck is in as well. This could take a while to find.
Dealerships, most of them anyway are paid piece work and diagnoses doesn't pay much and most don't know where to begin so they may not have tried very hard either.

 

Thanks for the reply Marten, it's still unresolved. The problem is it's not repeatable. I've recently replaced the alternator and both batteries. Have a good mechanic that kept it for a couple weeks monitoring it, everything checks out as OK. The dealership here is unacceptable so that's not an option. Im getting a cig-lighter volt meter like CathederalCub suggests so I can monitor it more closely.

 

Dose it have a car alarm or remote start?
I know alarms flash lights and if it is going bad maybe just the lights are on and closing the door jiggled it to stop the lights?
It could also be why the no start when you stopped for gas / coffee.
Just thinking out loud here
Good luck
Dave ----

 

The aftermarket conversion complicates troubleshooting. Grounds and parasitic draw are a good starting point. But as noted, experts have looked at it and not found an obvious problem. I would eliminate any added electrical items added by Sportsmobile and try to get wiring diagrams from them. However, OEM wiring has also caused crazy electrical problems.

 

I thought this was a fluke but it has come back today. Since my original post I've had it thoroughly checked out by an electrical expert mechanic. I have a lot of confidence in him, he did not find any problems but we replaced the batteries anyway (they were getting old), and since then it has not reappeared until today. A couple of days ago I had hauled a bunch of miracle grow garden dirt and pulled into the garden area to unload and just left the van there. Today I was getting the garden beds ready for planting and as I was walking up to the van the brake lights magically came on. I hadn't touched it since last week. I was looking right at it when they came on. I've got about 5 acres and half that is a hay field. I know there are no mice or rodents because we have feral cats everywhere, so no rodent signs and no chewing on wires. It wasn't locked and I didn't have the keys in my pocket so no accidental push of the remote. I pushed the brake pedal down, released it and then pulled on it to see if there was any sticking but it is back to top of the pedal travel with no issues there. The brake lights were then off on that one application. I did get a plug in volt meter and put that in the accessory port and it reads 12.2. This is the strangest thing I've ever had with any car I've ever had.

 

You did not reply to the alarm question. Does it have an alarm? It appears that something aftermarket is not working properly.

 

You did not reply to the alarm question. Either the OEM vehicle security module or aftermarket alarm may be the cause. Do the tail lights flash when you remotely lock the doors?

**edit**
The VSM will flash the tail lights with a lock command. If you have remote lock/unlock and it is OEM, you have a VSM. My guess is your VSM is bad.

 

Thanks for the reminder Don, no alarm, no remote. The van went from Ford to Sportmobile when new, so that's all 20 years ago. Currently only 56K miles, but I drive it just about every week. It has circuit breakers for the camper side of it, a main breaker, then refrigerator, A/C, and water heater. All those are left off unless camping. When it's shifted into 4x4 there is a light on the dash that comes on. There's a set of Hella driving lights for front and rear so there's switches for those. That's it, and all that was done 20 years ago. I just can't wrap my brain around brake lights coming on without any human input.

 

If your van has Advance Trac, there is a stability traction control relay that has power all the time and is truned on by the ABS module. If the ABS is faulty maybe it is sending power to the brake lights.

See if you can pull any DTCs (codes) from the ABS module. However, I don't know how to troubleshoot or repair the ABS module.

 

No ABS and the 4x4 conversion is by Sportsmobile. A Duratrac front axel, with manual Warren hubs, and an Atlas transfer case on 33 inch tires. The only thing electrical is a light on the dash when the front axel is in gear. My mechanic didn’t get any codes when he went through it after the September episode. I only have FORScan Lite on my IPAD and checked it today but that version is fairly limited, no codes.

 

There must be a wiring problem. Bad connector, shorted wire, etc. The aftermarket stuff makes this even more likely. Troubleshooting may require inspection of the wiring. If you catch it ON again, I would carefully and systemically pull fuses, except for the brake light fuse, to see if any of them kill it. If none do, then it's wire/connector inspection time.

 

Also, are you sure about the ABS? 2006 should have ABS ....but I'm no expert.