Brake Controller Question

[dapperdan]

I have a Braking question for the Gurus on here. About three or four weeks ago I got an "OL" read-out on my Prodigy 2 brake controller, checked online and started checking the "easy" stuff first. My socket in the bed of the truck was a little dirty so I cleaned that up. The plug had a little dirt in it as well so I cleaned that up. Trip back home from that campground and all "seemed" well. Next trip out I got the dreaded "OL" read out again.
Next I checked the wiring on the back of the truck, low and behold I did have three bad connections, although my running lights, signals and brakes lights were all working at this time the pin that supplies constant voltage to the trailer was the worst, in fact it broke apart after "giggling" it a little. Spent the better part of an afternoon redoing the wiring on the back of the truck. Another trip to a campground, thinking I solved my mystery and still getting the "OL" and now and then "SH" read out too!

I tested all the connections at the plug in the bed, all have good power except the brake pin, that one appears to be about half as bright (when tested with a continuity tester) as the rest. Traced and tested the wire all the way back to the cab, still half bright on the tester. Checked the power coming right out of the controller and that appears weak as well. The trailer brakes are pretty weak, I tried dialing up the power to them and even at "11" on the read out they grab "OK" but not like I think they should.

Today I pulled off all the wheels, checked the brake wires on all and repacked the bearings. Brakes look good, wires look good so what's my problem? I'm thinking it's the brake controller at this point, I've checked everything I can think of. What have I missed?

Thanks for your input.

Dan

[dapperdan]

Finally got my problem solved! The repair shop where I took the trailer (my dealer is on the other side of Chicago) "claims" they have the proper testing equipment. In fact they even called Tekonsha for the parameters for the Prodigy 2 and they "thought" it was reading/sending properly. Went through the entire wiring system on our trailer and couldn't find a wiring problem. Re-checked my truck, nothing. Short story, the controller went bad, they replaced the old controller for a new one and viola, I have a trouble free trailer again!!

When I called to check on the progress of our trailer they had asked me why "I keep adjusting the power all the way up on the controller". I told them I hadn't touched the adjustment! That's when the light went on! NEW CONTROLLER!

In their defense they work mainly on motor homes but I'm wondering if that was the right place to take my trailer.

We leave Saturday for a 5 week trip to the west coast, I don't need/want brake troubles when we get out of the flat lands.

Dan

[mapguy]

Gene&Ginny wrote:

dapperdan wrote:
... On the "blue" brake pin however I'm only reading 3.5 to 4.5 volts. ...

If you are not moving and press the brake pedal that is what you get if nothing is connected. A small voltage is sent through a high resistance in the controller to sense if the trailer is connected. The high resistance in the controller means a very small current so the brakes do no operate but the controller can "see" the magnet wiring in the brakes. It will go higher if you are actually moving and hit the brake pedal to stop (inertia). Operating the manual lever will vary the voltage too.

Usually problems like that are where the brake wire passes through the wheel and the insulation cracks causing a momentary short to ground which the controller "sees" as an overload or short circuit.

This is correct. No controller output unless the controller senses the magnets being in place and wiring intact with PWM.

Clearly, the OP has a wiring problem. Very rarely will the tow vehicle side and or the controller be faulty with these symptoms. Very surprised that your RV Dealer does not have a Tekonsha Brake Controller test box...

Minor wire cracking and chafing is difficult to inspect -many times it is cheaper, when paying for mechanic labor, to to run new wire and connections from the front axle drop splice and back including the axle(s) crossover sections.

Has the dealer pulled the brake drums and looked closely at the magnet leads? This is the next likely place for a problem wire.

I have been through this drill many, many, times from working in a mixed fleet (large rental fleet) environment. Can be exasperating....

[Gene_Ginny]

dapperdan wrote:
... On the "blue" brake pin however I'm only reading 3.5 to 4.5 volts. ...

If you are not moving and press the brake pedal that is what you get if nothing is connected. A small voltage is sent through a high resistance in the controller to sense if the trailer is connected. The high resistance in the controller means a very small current so the brakes do no operate but the controller can "see" the magnet wiring in the brakes. It will go higher if you are actually moving and hit the brake pedal to stop (inertia). Operating the manual lever will vary the voltage too.

Usually problems like that are where the brake wire passes through the wheel and the insulation cracks causing a momentary short to ground which the controller "sees" as an overload or short circuit.

[dapperdan]

RCMAN46 was right, I had a wiring problem, still do. Took the the trailer to an RV repair shop early last week to let the "experts" look into my problem. They "thought" they had the problem solved (bad connection by the pin box) so I picked up the trailer and had no troubles on the way home. We decided to go for a short (near our home) camping trip, on the way there no trouble, on the way back the dreaded "OL" message again! Dropped the trailer off last Thursday, they started on it yesterday (Monday), went through the entire trailer, brakes, magnets wiring everything according to the service tech. Can't find anything, or so he says, tomorrow they want the truck back so they can re-check that. They even called Tekonsha about what they believe is a false reading. I (we're) hoping it's the controller itself, I even asked the tech about switching out the controller just to see what happens with a new controller so that's one of the things happening tomorrow. Got my fingers crossed!

Saturday we were supposed to take off for a five week west coast trip, not so sure that's going to happen on time now.

I'll post what ends up happening.

Dan

[RCMAN46]

You have a wiring problem!

Take a careful look at the installation instructions. A OL and this is direct from the instructions is "Prodigy P2 “sees” an overload condition during operation."

A SH also direct from instructions is" 1. Brake wire sees short during idle condition.
2. Use of some test lights or non-Tekonsha testers
can cause this problem."

Because of the way a PWM inertia proportional device works cheap voltmeters do not give accurate readings.

As you will be advised to do you can junk the Prodigy and install a Max Brake then after spending big bucks you can fix the wiring problem so the Max Brake will work.

The P2 does have a limited Lifetime Warranty. Suggest you look it up on their website and you will see they offer the best warranty in the business. Even the Max Brake does not offer a lifetime warranty.

[dapperdan]

Thanks for the tips!

I did look at the wires running into the axles, from what I could see (although not that much) the wires looked and felt perfect. This is a 2011 Montana that we picked up in late 2011. We don't even have 6,000 miles on this trailer!

This morning I did take a voltmeter out to the truck and checked the voltage at the plug-in. I get 12.7, 12.8 volts on the signals, the brakes lights and the marker lights. On the "blue" brake pin however I'm only reading 3.5 to 4.5 volts. I tried turning up the power on the controller and nothing happened, no increase in voltage any way. I'm wondering if it's my controller now.

More research I guess.

Dan

[j-d]

mapguy echoes a tip I got from an RV tech. The tubular axles rust inside and the rust chafes through the insulation of the brake wires.

[mapguy]

OL is the blue brake feed wire shorting to ground. SH is lost ground connection. You have wiring issues somewhere. Probably between the trailer male plug and the brake magnet connections -yes this is a long vague area.... A good place to start is the cross over wire run inside the axle. These are known to fray and cause problems like you describe. I never run wire back inside the axle tube -hang it on the back upper part of the tube. Every connection is suspect, too. Especially if they are not "sealed"

[pkunk]

Mex, are you smokin' funny stuff tonight?

[j-d]

How often do people die in this neighborhood?

Same as anywhere else. Once.

[MEXICOWANDERER]

So this means a limited lifetime is warranteed? Shoot why not say a limited lifetime is GUARANTEED? He he he...

[j-d]

Thought maybe I could help you, but when I downloaded Brake Controls from Cequent (Tekonsha) website under "Support" what I got was a Catalog.
I know you don't want to wait, but you may need to call Tekonsha. I did, and they were very helpful. Also noticed on Catalog that Prodigy, at least the model they sell now, carries "Limited Lifetime Warranty."