Help! No Brakes on New 30' Classic!

[LittleRadio]

My father just bought a new '05 30' Classic. He has a Prodigy brake controller.

When driving at walking speeds, he can activate the trailer's brakes via the brake controller. But when he gets up above 30 mph or so, it feels as if the controller isn't sending enough current to the trailer brakes to help stop. In fact, above 30 mph or so, his truck is doing ALL the braking.

(Yes, I plan on posting his commentary of '05 quality to the thread that's established on this site).

He just left DonMar in Lynchburg, SC, and they could not find the problem. They switched brake controllers -- same symptoms. Brakes work at low speed, brakes can't get enough juice (or just don't work properly) at higher speeds.

What could this be? My father's going to monitor this thread once he gets back and settled at the campground in Myrtle Beach; so let the ideas fly! It'd be great to have brakes for his trip back through the Allegheny Mountains!!

Thanks!

[Silvertwinkie]

Has he calibrated the unit yet? You need to be in park and take the manual level and pull it all the way to the non resting place on the unit. Adjust the power to about 6.6-6.7 with the rolling dial on while holding the manual brake level, then try doing further adjustment to your liking from there. Being that it's a new coach, it should not need any boost, and although 6.5-6.6 is suggested by the manufac, I found that about 6.8 is a good place with our 25'.

Keep in mind it works with inertia, so unless you are hitting the brakes, it might not always show any or much current. Another good test would be to allow the unit to roll just a bit and move the manual bar all the way to the opposite on the Prodigy and you should feel the brakes on the trailer grab good and hard....remember not to touch the tow vehicles brakes when doing this......

Hope this helps.

[rluhr]

Does he have the boost set properly on the Prodigy? For a 30-ft Classic, it should be at B2 setting or higher, I would think. The full calibration sequence is in the documentation and I would go through it one more time, very carefully. It is easy to misunderstand, the way Prodigy has written it.

[LittleRadio]

My father's 30' Classic was built in October of last year, so even though it's an '05, it's got the drum brakes -- not the disc ones.

The service tech at DonMar called Airstream and explained the loss of braking ability, explained how they replaced the brake controller, pulled the wheels, examined the brakes... The Airstream rep was flummuxed and could only suggest that my father bring it back to Jackson Center on the way back home to Michigan.

Still seeking ideas... thanks again for the posts. I've been e-mailing them to my dad as he drives back to the campground with his AS.

[jcanavera]

The controllers job is send voltage back to the brakes. More voltage more braking. The inertial side comes into play since as you increase the braking pressure the controller senses the "lean". Much like you feel yourself being pulled forward as you step harder on the brake. As that force increases the controller is supposed to ramp up the voltage back to the brake magnet which will increase the braking.

Ok so it works at low speed. Probably not too much if any inertia at that point. What ever braking being applied to the trailer is based on the gain that was set. Obviously as you go faster and have to push harder the trailer brakes should be activating more strongly.

If I'm not wrong (and those of you with this controller chime in), doesn't that controller have a visual screen showing the amount of power being sent back to the brakes? Normally when you use the manual lever to activate the brakes the same screen shows the power being applied. Now if he can get up to 30 mph or so and apply the brakes fairly aggressivley, he should see that voltage ramp up. Now he can do the same only this time don't step on the brake, but instead use the manual lever on the brake control. He should be able to see that power again ramp up. Dependent upon how the gain was set (as the others have told you), and how far he activates the manual lever, he may be almost able to get the trailer wheels locked up. My point here is to at least determine whether the inertial system is providing similar amounts of power back to the brakes as the manual activation does.

If you see similar ranges of power being applied, I would guess that you now need to look at measuring power applied to the brakes themselves. Again the manual lever depressed or moved to its max position should apply full power to the brake magnets. While the trailer is stationary did any one at the dealer do this measurement? I would think that this test would verify as to whether the voltage from the controller is being delivered to the brake magnets. You would almost need to check each magnet to be sure all is ok here.

If the power isn't there, it becomes a matter of back tracking towards the tow vechicle and measuring power. The key to me is if the manual lever activates the brakes. On my controller the instructions on setting up the gain have me get to about 25 mph and then push the manual control to full on. The trailer tires should almost go to full lockup. We did this test on the dealer's parking lot. If you can't get to a lockup or at least a very noticible trailer brake application, you know you need to start some measurements.

I a little concerned that a dealer couldn't track this down. This is pretty simple electronics here once you get past the controller.

Jack

[dmac]

What does the Prodigy's display read when braking at slow speeds vs braking at higher speeds? The display shows the voltage being delivered to the brakes.

Tekonsha's technical support number is 888-758-5832.
The Prodigy Owners Manual is available online at: http://www.tekonsha.com/instructions...89_H%20web.pdf

[LittleRadio]

Ok, so my father ran into a very intelligent RV guy at the campground he is staying at.

After explaining the symptoms to this gentlemen, he tells my father it could only be due to three or four things... and he proceeded to rattle them off.

My father, an engineer, immediately recognizes one as the most likely culprit: a bad ground.

You see, voltage reads as it should, but if you have a bad ground, not enough current will make its way back to the trailer brakes. This is most likely the culprit because the SE Michigan Airstream dealer who sold him his rig and made the BC connections completely botched the whole job... cutting into the tow vehicle's electrical system when they shouldn't have. (They also sent him on his way without sway bars or locking washers on the hitch ball assembly... boy, have I got some "bad dealer" posts to put up later on when my father gives me a post-mortem).

Anyway, he's taking his setup back to DonMar to have them fix it. Thanks to all who contributed ideas or spent time pondering it. Let's hope this is it!

[jcanavera]

Originally Posted by LittleRadio

You see, voltage reads as it should, but if you have a bad ground, not enough current will make its way back to the trailer brakes.

OK. That makes sense. I guess I'm wondering whether the Prodigy controller was able to sense this. If you would lose the ground then for sure the unit displays an error indication. I'm not sure what happens on a marginal ground. I always thought a bad ground is either a situation where it is or isn't there.

Jack

[LittleRadio]

ground wire could be frayed, with only a few strands of wire in constant contact with ground. We'll see what DonMar finds out.

[joatmon]

The interesting thing about trailer grounds is that, while they are supposed to made with the white wire at the umbilical connection, simply hitching up the trailer will also complete the circuit as far as taillights go. In my limited experience, the white wire is usually tied to ground at the trailer.

If the brake problem is a bad ground, the bad connection would just about have to be where the brake wire from the umbilical splits into the individual wires run to each magnet. If the connection is bad, the belly skin may have to be dropped to access it.

[alvinator]

I had the same apparent lack of braking force on my 2005 28 classic. I had my local RV center check everything while my unit was getting PA inspected and he could find nothing wrong.

I cranked up the Prodigy to max voltage and started using it. The braking seems to be getting better as I have been able to lower the voltage to about 9 and the unit is braking well.

It appears to me to be just a break in issue.