Forest River Forums

Forest River Forums (
-   General Community Discussions (
-   -   Truck problem -anyone a mechanic out here? (

mn_308 04-12-2007 09:09 PM

Truck problem -anyone a mechanic out here?
Due to some late season snow/ice I’ve been driving my truck the last couple of days.
Truck = 2004 Ford F-250, 6.0 Diesel.
Auto transmission, and I noticed when putting it into reverse it wouldn’t actually go into reverse immediately.
Next I noticed that while in Park and stepping on the brake pedal, the speedo is actually measuring ~10mph!
Dealer wired my Prodigy last winter, but I didn’t actually mount and plug it in until a couple weeks ago.
Don’t know that I’ve used the truck since I did that (or at least didn’t notice these issues).
With that in mind, I removed/unplugged the brake controller, which seemed to make the issue go away.

I need to test this further, but though I’d throw a post out here, for suggestions from those with experience.


(edit to include truck model/year - thanks Bear!)

Bear 04-12-2007 09:17 PM

What brand/year of truck??

mn_308 04-12-2007 09:36 PM

'04 Ford F-250, 6.0 Diesel

(I'm blaming the cold I have for leaving out this bit of info...)

budfans 04-12-2007 09:52 PM here is a web site that can help ford truck owners it's a forum site and it is large hope it helps.

milzat 04-12-2007 10:21 PM

You could contact Tekonsha(manufacturer of Prodigy) HERE. They may have run across this problem before.

mn_308 04-13-2007 09:07 AM

Thanks Team!

I'm a member over at, but mostly just lurk there, maybe I will post to see what I get for feedback.

I did send an email to Tekonsha.

If I have time today, I may stop by my dealer also, and ask them.
(maybe see if I can test with a different controller, to see if behavior is the same)

MrSen 04-13-2007 06:08 PM

I have never heard of " for the link. I am a member at f150online only because I have an 06 F150

Now, I know the f250's need to have the prodigy or any electric brake controller grounded seperately, I know this only because I have read it over at f150online and I have the same controller.

Maybe do a search there, they have a section for towing and for f250's gas and diesel.

Sounds like a ground problem to me, but I am no mechanic.


mn_308 04-13-2007 07:55 PM


I think I’ve got a membership over there also, from my last rig, just haven’t been there in some time.
I bumped into the separate ground mention somewhere along the way, and that is my next step.
After spending a couple of hours crawling around that truck, checking every plug/wire I could find, and re-soldering connections (Ford OEM harness spliced to Prodigy provided harness) I was truly frustrated until I sat down here and saw your post.

Left work early to stop by my dealer to chat with the techs, they treat customers (at least me) very well.
Explained the situation, told them I had spoken with Tekonsha on the phone, and they thought it was probably a short near the trailer connection do to recent climate (salt, sand, wet…). The dealer disagreed, but suggested running to a solid ground. They even opened up a new Prodigy which we plugged in to confirm that it wasn’t the controller itself.

Step 1 - go to store for some beer
Step 2 - go back to work on the truck…

mn_308 04-13-2007 09:41 PM

I'm about at my wits end with this!
Ran from the ground wire on the Prodigy straight to the negative battery post, and the misbehavior is still occurring.
Worst part is how inconsistent it is.
In Park, step on brake once, speedo jumps, second time, nothing, third time, nothing, then speedo jump on release of pedal...(just an example, it's not repeatable at all).
Thought I was onto something when I had the boost feature set on 3, as every tap on the brake pedal would 'bounce' the speedometer, but then that stopped after a couple of taps on the pedal.
GRRRRRRR.... I'm done for tonight.

Maybe tomorrow I'll have a chance to tackle this again, when I am a little more fresh in both mind and body.

MrSen 04-15-2007 08:57 AM

WOW......looks like you tried almost everything........keep plugging away at it, I know it can be frustrating at times but sounds like you are trying everything.

Maybe do step 1 a few times Let us know how you make out and good luck.


dimurrrw 04-16-2007 08:01 AM

I'm not a mechanic, but two possibilities come to mind since you say that unplugging the controller makes the problem go away and plugging in a new controller does not change the situation.

1) Try spraying the interface (plugs) between the controller and the truck's computer with electronic parts cleaner. You can probably find it at Radio Shack.

2) If that does not work, ask the Ford dealer if he can flash the truck's computer. It occurs to me that the problem might be there.

BTW Does the problem persist when you connect the trailer to the truck?

aintgotnun 04-16-2007 08:28 AM

You mentioned that the dealer installed it for you "Ford OEM harness spliced to Prodigy provided harness". Have you double-checked their work against the instructions that came with the controller? You mentioned re-soldering the connections but............. Are the wires in the right order? Or maybe, just maybe, the OEM wiring harness is messed up. Also there are "preconfigured" wiring harnesses for the Ford Prodigy combo for just a few buck.

good luck and let us know how it turns out

mn_308 04-16-2007 04:12 PM

Thanks to all for the suggestions.

Already checked connections, everything looks good.

Spoke to service mgr at my Ford dealer, he had no ideas, and sounded like they wanted the truck for a day to diagnose it (I'm sure that would be a nice invoice in the end...)

The tech at the RV dealer used crimp on butt splice connectors, between the harnesses. I cut these, and soldered the connections to guarantee that this was not the issue. I'm fairly certain that wires are correct, both on the connections the RV dealer made, and on my improved connections.

More details in my thread over on
Quotes from that thread:


Originally Posted by mn_308
This is making me kind of crazy…

Tested with another prodigy controller (new), and the speedo still bounces.

Good solid ground (straight to negative post on the battery).

Everything looks right and it still continues it’s random misbehavior.

If I unplug trailer wires from the harness under the back of the truck, near the spare tire, the problem still occurs. Leads me to believe that the last section of harness, and trailer connection is fine.

If I unplug the harness which leads to the trailer connection from under the hood (comes into a plug on drivers side, near the firewall and fender), the problem seems to go away. Not sure how something could be wrong here as all the wires in this bundle are well wrapped and run along the frame rail. I can’t see any damage after a fair amount of time crawling around underneath…



Originally Posted by mn_308
I agree, something is bad in that one stretch of harness.
I suspect that running a new brake wire (and maybe a new ground also?) will remove the problem.
That's probably going to be quicker and cheaper that a new harness, and provide the same results.

All times are GMT -5. The time now is 08:55 PM.