Prodigy display question

MarkLeininger · Jul 30, 2008

When I hook up my trailer, prodigy displays .c. as it should. After driving awhile it starts displaying low numbers (0.4-1.5) with no brakes applied. As soon as I apply the brakes it displays .c. The manual lever works properly and stops the vehicle gradually when applied.

As I recall it used to display the voltage when the brakes are applied, and .c. when they're not applied, the opposite of what it's doing now. Any thoughts on what's wrong?
thanks

David Ferguson · Jul 31, 2008

Is this a new installation, or has it ever worked correctly? If it's new, then I would think that you have the brake switch connected incorrectly. (probably something like the brake switch & ground swapped).

If it did work correctly in the past, then check that all wiring is still attached, you haven't got a burned out tail light bulb, bad ground on your trailer, etc.

AlanB · Jul 31, 2008

They have an EXCELLENT help line.

If anyone has seen that problem, they have, and have walked me through a couple real quick.

Oh, and your statements are correct, it would appear to be working backwards from what is normal.

MarkLeininger · Jul 31, 2008

David Ferguson said:
Is this a new installation, or has it ever worked correctly? If it's new, then I would think that you have the brake switch connected incorrectly. (probably something like the brake switch & ground swapped).

If it did work correctly in the past, then check that all wiring is still attached, you haven't got a burned out tail light bulb, bad ground on your trailer, etc.

It has worked correctly for a long time, this is new behavior. I sent email to the Tekonsha helpline, they got back to me right away. They suggested checking for 12v on the brake output wire when I apply the brakes, 0v when the brakes aren't applied, to see what's actually going on. That's easy to measure so I'll check it out tonight. I spend more time fiddling with trailer electrical problems of one kind or another than I do anything else around the house.

escavader · Aug 2, 2008

MarkLeininger said:
When I hook up my trailer, prodigy displays .c. as it should. After driving awhile it starts displaying low numbers (0.4-1.5) with no brakes applied. As soon as I apply the brakes it displays .c. The manual lever works properly and stops the vehicle gradually when applied.

As I recall it used to display the voltage when the brakes are applied, and .c. when they're not applied, the opposite of what it's doing now. Any thoughts on what's wrong?
thanks

MARK,
Mine displays 0 0 when not stepping on the brake,and then when i do, the harder i push the higher the number,until i get to the max that i set it at.Ihave the dvd i might be able to find out an answer to how to set it up.Ido recall they recommend 6.0 as the baseline,and you adjust from there.As far as wiring my TUNDRA is a plug and play,i had nothing to wire up.
ALAN

lovemytoys · Aug 2, 2008

escavader said:
MARK,
Mine displays 0 0 when not stepping on the brake,and then when i do, the harder i push the higher the number,until i get to the max that i set it at.Ihave the dvd i might be able to find out an answer to how to set it up.Ido recall they recommend 6.0 as the baseline,and you adjust from there.As far as wiring my TUNDRA is a plug and play,i had nothing to wire up.
ALAN

did you buy the one for tundra .im looking at getting one for mine

escavader · Aug 4, 2008

lovemytoys said:
did you buy the one for tundra .im looking at getting one for mine

The wiring plug in was for my 08 TUNDRA,just plug it in and thats that.I mounted it in where the ash tray was[non smoker here]it looks like it was made to be there.
ALAN

MarkLeininger · Aug 9, 2008

I finally had time to look at this. There are two problems, one is that the display is not representing what's going on at the connector. When I apply the manual lever it does show 6v at the connector, and the brakes do work, but the display continues to read .c.
When my trusty assistant steps on the brakes, the voltage does range up to the maximum as it should at the connector, but the display stays at .c.

The second problem is that when the brakes are not applied the display reads about 1.5v, and that's what I see at the connector. Brake system (2 axles) reads about half an ohm, but that's measuring with a crappy meter so it's probably in the ball park. I think those magnets are supposed to be about 50mOhm each, plus some resistance in the wiring. I can also activate the brakes with the breakaway switch and they work properly.

I sent another email to tech support with all this additional info, but it sounds like the unit is not working properly.

MarkLeininger · Aug 17, 2008

Problem resolution: talked to tech support, they said to check voltages at the prodigy connector. Should be 0v if the brake is released, 12v if it's depressed. I wasn't sending 12v when the brake was depressed because the vampire tap I put on the cold side wire of the brake switch wasn't making contact. Fixed that and everything's fine.