Trailer Fault problem this weekend... - Montana Owners Club

Art-n-Marge · 03-08-2010, 07:12 AM

On the return trip home my Ford F-250 reported a Trailer Fault as I was on a long downhill of I-15. Even though I use Tow/Haul, if the downhill is long enough, I need to depress the brake pedal to cause the downshift to slow the rig down as it gains speed. But this time I got a Trailer Fault.

We were less than 10 miles from home, so we were able hobble home and tried to drive in such a way that I did not have to brake hard, but when enough pressure was applied on the brakes the Trailer Fault would sound once again.

I will hitch the truck and jack up each side in order the check out things starting with the wiring. I will be examining the brakes and hope that some of you can give me some tips on your experiences. I do have the integrated 2006 Ford F-250 brake controller (OEM'd from Prodigy) but do not expect that it is so different from other model vehicle integrated controllers or even the discrete controllers from many manufacturers so everyone's experiences and knowledge would certainly be appreciated.

Crossthread · 03-08-2010, 09:06 AM

Art, My money is on the right rear brake actuator arm that has cut into the magnet wires.Bill

David and Jo-Anna · 03-08-2010, 01:31 PM

I echo Bill's pointing to damage to the wiring on the right rear brake actuator--that's what caused us to get the "trailer fault" warning when towing with our F-350 last fall.

Art-n-Marge · 03-10-2010, 04:12 PM

Haven't found any problems yet - right side pads looked good, wiring and magnetics looked good (and so do the bearings for that matter) but I still have two brake assemblies to check. While I was at it, does anyone now the minimum thickness for the brake pad? They still look okay, but they certainly don't look new.

I just thought of something. I have a sneaky feeling that my problem will be the 7-pin connector in the truck bed. I think I'll just take the rig out for a spin and use the 7 pin at the bumper instead of the one in the bed and see if the problem goes away. I've had trouble with that connector twice before with other connections.

KTManiac · 03-10-2010, 06:06 PM

Art,

Was it raining, wet out, or did you pull through any deep puddles when this happened?

Art-n-Marge · 03-10-2010, 07:23 PM

Yes it was raining, had been raining but I drove about 50 miles and by that time the rain had stopped and the roads were starting to get dry for about the last 5 miles, then the downhill and the trailer fault finally occurred when I hit the brakes to force the downshift of the Tow/Haul. I did wonder if there was some residual water left over somewhere in the Brake electronics.

I am also afraid the problem might go away if things are dry which means I may not be able to reproduce the problem until next winter when the rains come back.

Farmhawk · 03-12-2010, 03:06 PM

The only time mine has ever faulted was in the rain, but it was towing a car trailer plugged in at the bumper.

**Rondo** · 03-12-2010, 05:49 PM

Art-- Sounds to me it is in the 7 pin connector especially if it was raining! I've had problems with my connection in the box connector also and I've mainly found out that it is not in totally secure or that some moisture has gotten in and shored out a pin. I've even had one side of the Monte lights work and the other not working. I go to the umbilical, pull it out and reconnect and for some reason the all the rear lights work! All it takes is a fraction of an inch of one pin to cause a problem or just one drop of moisture on a pin.

junglejim · 03-13-2010, 12:52 AM

Art, I went to a Ford dealer here in central Florida and was talking to the service manager about different things. And in our discussion he asked me if I ever had a trailer fault. I told him no. Anyway he said they are common and most of the time it is the connector and pigtail. He told me to get a can of contact cleaner and clean both every so often, thats what causes most of the faults they have seen, a little dirt or moisture, just like Rondo says.

H. John Kohl · 03-13-2010, 02:29 AM

Art,
Take a compass with you, hook up the 7 pin to the truck and have someone step on the brake. Now Take the compass and walk past each wheel with it about six inches (distance not critical) from the wheel. The compass should act like a stud finder and point at the center of the axle for each wheel. If it does not for one of the wheels then that will tell you the magnet wires are separated. That is the quickest way I know to check the magnets on each brake.

Let us know what you find.

Waynem · 03-13-2010, 04:06 AM

Darn John! You must live in a round box and can see all angles.

Nice tip.

Tfthorp · 03-14-2010, 07:26 AM

Only time I have had a trailer fault was in wet weather and bumpy road which tells me it is a connection issue. 07 f350

Art-n-Marge · 03-14-2010, 07:12 PM

Thanks for all the tips. The ones about the rain or connector issue are sure sounding like the culprits. It had been raining a lot and an undercarriage check out showed all wires in good shape (not frayed, pinched or cut wires). The brake shoes were worn down but still usable and adjusted well.

When I get some time I will be trying out the magnet trick that a couple of you have mentioned and I will even try the connector at the bumper. I used the Monty dealer installed bed connector and have had other problems with it in the past caused by loose connections.

capn chris · 03-15-2010, 05:42 AM

Art,
When I'm towing I run w/my lights on. That keeps trailer lights on, too. I can glance in my side rearview and see the Monty side lights on. If they go off, I've got a connecter problem...loose. Stop and check. I also used a flat screwdriver to adjust my cable terminal connecters so they hold better (bent them closer together). Worked for me. Good luck.

bjj5633 · 03-15-2010, 11:27 AM

The only time I had a trailer fault,The trailer brake cord pulled out,Maybe you have something wrong with that.

Art-n-Marge · 03-28-2010, 05:14 PM

I think I am going to chalk this up to the rainy driving. This is only the second time driving in a hard rain since owning and using the rig and this was by far a worse rain storm than the first time. We just came back from a short trip and did not have any trailer faults compared to the many I was having on that day. But the weather is clear, warm and dry and the trip was short.

Thanks for all these tips. I do drive about 90% of the time with lights on, but I will now make it 100% (Cap'n Chris - I did have the lights on and didn't see any issue at the time). I will add using contact cleaner on the connectors before every trip to make sure contacts are as true as possible.

Before this recent trip, I did examine the brakes and found nothing wrong (what a pain that was) using some of the techniques mentioned.

I guess the biggest concern I will have when driving in the rain is at the next trailer fault, does this mean I am really having a trailer fault and the brakes are still working or not? In any case, I will have to apply brakes much sooner and hope no panic stops occur just to be safe. I am not completely happy about this, but I sure know more about the possibilities with all your help. Thanks very much.

richfaa · 03-29-2010, 03:40 AM

Art..Did you get in that junction box up under the pin box. Everything goes through there and it is a rats nest. We had to get in there and separate / reroute the wiring. Never had a problem since.

deadeye · 03-29-2010, 04:27 AM

Art:
I don't have a Ford but I suspect that the rainy weather is the culprit. On mine - a GM product - the cruise control quits working when the connection is bad.
I just take the connector apart and spray with a water absorbing spray that you can get at most Auto Parts Stores. We use to use it on the inside of distributors to dry them out...JB

Art-n-Marge · 03-29-2010, 01:43 PM

Yup Rich, I've checked the junction box back when I was having other wiring problems and that all seems to be cleaned up pretty good. It included tearing apart all the wiring the RV dealer had done and after finishing it off better than they had, that seemed to clear up my other wiring problems.

I do plan to add the connector spray procedure to my trip checklist along with cleaning the contacts and bending them out to make better contact. Any suggestions on what spray product works best would be appreciated.

DnDatGrdJct · 04-07-2010, 09:59 AM

Art,

I just took my 3075RL in for a new pinbox, tires and general service. On the way to the service center I had a message on my digital readout that there was a trailer brake failure. I have a Chev with built-in controller so it is different than yours. However, when I mentioned the problem to the service manager his first question, is it a Ford. He also stated that in almost every case he has seen this it is with a Montana Unit. He said that the factory installed controllers are extremely sensitive and even a stray single strand can cause this problem. He also said that Montana has this as a rather common problem.

After checking everything they found nothing with the trailer brakes so his next check is on the truck itself having a defective controller. Since we have had no rain I can not blame that as a factor.

Hope that you found the cause of your problem and have it fixed.

Dean

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