Notices
1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

electric brake control question

Thread Tools
 
Search this Thread
 
Old Jun 27, 2012 | 09:04 PM
  #1  
firewood truck's Avatar
firewood truck
Thread Starter
|
Senior User
Joined: May 2011
Posts: 422
Likes: 0
From: Charm City
electric brake control question

I'm in the middle of setting up my '90 F250 w/ an electric brake control. It doesn't have any factory provisions for trailer wiring so I've been doing it all from scratch. I ran a full harness from the 7 pin connector straight up the chassis into the engine bay. Tonight I got the main wires tied into the system so now when I step on the brake pedal the red LED glows on the brake controller.

I jammed a windshield squeegee into the brake pedal so that I could measure the voltage at the pin on the 7 way. I only got about 3 volts. My question is- is this normal? I'll get a helper tomorrow and measure the voltage with the 'emergency stop' level pushed all of the way over to see if I get a full 12V but I have no idea of how much voltage should be back there when just the brake pedal is applied.
 
Reply
Old Jun 27, 2012 | 09:17 PM
  #2  
Diesel_Brad's Avatar
Diesel_Brad
Fleet Owner
15 Year Member
Photogenic
Liked
Loved
Joined: May 2009
Posts: 21,437
Likes: 76
From: Gilbert, PA
Depending what brake controller you have, 3v is all you will get. Alot of controllers out there have a pendulum inside to swing forward(when moving and brakes applied) and this will send more voltage to the trailer the farther the pendulum swings. It is really a STUPID idea. If yo hit and hold the override, it will send the full 12v to the trailer

I really like brake controllers that read the trucks brake pressure then sends equivalent voltage to the trailer. That way the truck and trailer stop in unison
 
Reply
Old Jun 27, 2012 | 09:24 PM
  #3  
firewood truck's Avatar
firewood truck
Thread Starter
|
Senior User
Joined: May 2011
Posts: 422
Likes: 0
From: Charm City
Thanks for the help. I had one of those hydraulic type of controllers years ago, it was probably the best controller I've ever had. I've always wanted to develop a hydro-electric brake system. It would use an inertia based electric controller which would operate an electric servo to push in on a master cylinder mounted on the trailer chassis. Think of it as a combo of a surge brake w/an electric controller.
 
Reply
Old Jun 28, 2012 | 02:50 AM
  #4  
RV_Tech's Avatar
RV_Tech
Hotshot
Joined: Jan 2010
Posts: 10,060
Likes: 491
From: Bristol, TN.
The electric over hydraulic brake system you describe already exists in some high end fifth wheels and yes, 3 volts is the normal maximum you will see using the brake pedal at rest in a brake controller with an accelerometer as found in all moderately priced to high end controllers.

You can buy a controller model that reads brake pedal pressure in your truck and operates the trailer's electric brakes, if you like MaxBrake™ - Hydraulic over Electric Variable Brake Controller

The best high-end electronic controllers do an amazing job of matching trailer brake output to the rate at which your truck is stopping and with their built-in diagnostics make troubleshooting a breeze.

My two cents,

Steve
 
Reply
Old Jun 28, 2012 | 04:36 AM
  #5  
Diesel_Brad's Avatar
Diesel_Brad
Fleet Owner
15 Year Member
Photogenic
Liked
Loved
Joined: May 2009
Posts: 21,437
Likes: 76
From: Gilbert, PA
I put a Maxxbrake in my pickup, It was by far and away the best $250 I spent on the truck
 
Reply
Old Jun 28, 2012 | 06:40 AM
  #6  
RV_Tech's Avatar
RV_Tech
Hotshot
Joined: Jan 2010
Posts: 10,060
Likes: 491
From: Bristol, TN.
[QUOTE=Diesel_Brad;12002166]I put a Maxxbrake in my pickup, It was by far and away the best $250 I spent on the truck[/QUOTE

Have never owned one, but owner reports seem consistently good.

Steve
 
Reply
Old Jun 28, 2012 | 09:51 PM
  #7  
firewood truck's Avatar
firewood truck
Thread Starter
|
Senior User
Joined: May 2011
Posts: 422
Likes: 0
From: Charm City
Originally Posted by RV_Tech
The electric over hydraulic brake system you describe already exists in some high end fifth wheels and yes, 3 volts is the normal maximum you will see using the brake pedal at rest in a brake controller with an accelerometer as found in all moderately priced to high end controllers.

You can buy a controller model that reads brake pedal pressure in your truck and operates the trailer's electric brakes, if you like MaxBrake™ - Hydraulic over Electric Variable Brake Controller

The best high-end electronic controllers do an amazing job of matching trailer brake output to the rate at which your truck is stopping and with their built-in diagnostics make troubleshooting a breeze.

My two cents,

Steve
Thanks for the reply! I don't know what type of controller I have, it came out of a parts truck from last summer, I'm sure it's not a high end unit but it will work for now. I will definitely look into the hydro over electric controller.
At least it seems that my hybrid brake system was a decent idea!
 
Reply
Old Jun 29, 2012 | 05:56 AM
  #8  
RV_Tech's Avatar
RV_Tech
Hotshot
Joined: Jan 2010
Posts: 10,060
Likes: 491
From: Bristol, TN.
Originally Posted by firewood truck
Thanks for the reply! I don't know what type of controller I have, it came out of a parts truck from last summer, I'm sure it's not a high end unit but it will work for now. I will definitely look into the hydro over electric controller.
At least it seems that my hybrid brake system was a decent idea!
Your hybrid system is interesting. What lots of folks who RV and have them don't know is the industry did not design them to improve braking ability, which they think electric brakes by themselves can easily handle.

The hybrid idea came about as they were searching for a way to improve reliability due to folks not maintaining their electric systems. From their perspective, the hybrid systems used disc brakes in RVs actually react more slowly than the all electric system as the hybrid has to operate a pump to activate the brakes. Not really a great difference, but I thought it was an interesting bit of trivia.

Steve
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

10 Ways Ford is LOSING to the Competition

 Joe Kucinski
story-1

Top 6 Best Deals Available on New Fords & Lincolns Right Now

 Brett Foote
story-2

This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

 Verdad Gallardo
story-3

Top 10 Fords at 2026 Carlisle Ford Nationals

 Joe Kucinski
story-4

3 Best / 3 Worst Parts of Modern Ford Ownership

 Brett Foote
story-5

10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

 Pouria Savadkouei
story-6

Every 2026 Ford Engine Explained

 Brett Foote
story-7

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-8

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-9

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
Old Jul 3, 2012 | 05:29 PM
  #9  
firewood truck's Avatar
firewood truck
Thread Starter
|
Senior User
Joined: May 2011
Posts: 422
Likes: 0
From: Charm City
I ran into an interesting glitch today. I accidently turned on the hazard lights and I noticed that the red LED on the brake controller was blinking in unison with the dash board indicators. It doesn't do it w/ the turn signals, just the hazards.

I'm gonna go out on a limb and assume that it isn't supposed to do this? I tapped into the 'cold' wire on the brake light switch for the brake signal for the controller so I'm at a loss as to what the issue might be.
 
Reply
Old Jul 7, 2012 | 12:23 PM
  #10  
EPNCSU2006's Avatar
EPNCSU2006
Lead Driver
20 Year Member
Joined: Nov 2002
Posts: 9,558
Likes: 45
From: Concord, NC
I think you need a "pulse preventer." You can probably find one at most places that carry electric brake controllers.
 
Reply
Old Jul 8, 2012 | 12:28 PM
  #11  
Phy's Avatar
Phy
Fleet Mechanic
Joined: Jan 2011
Posts: 1,709
Likes: 4
From: 8600 ft in Colo
Yup, you need a pulse preventer. The hazards are backfeeding the brake light circuit, and the controller thinks you're pushing the brake pedal...
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Wildcat313RE
6.7L Power Stroke Diesel
3
Apr 2, 2017 04:20 PM
beeser
1999 - 2016 Super Duty
0
Sep 6, 2016 03:48 PM
derekmj64
All Things Towing
4
Feb 13, 2010 10:58 AM
ultramag
1999 - 2016 Super Duty
6
May 15, 2009 09:30 PM
sty
All Things Towing
4
Jul 29, 2004 07:08 AM




All times are GMT -5. The time now is 02:37 PM.

story-0
10 Ways Ford is LOSING to the Competition

Slideshow: 10 ways Ford is losing to the competition

By Joe Kucinski | 2026-06-15 09:52:01


VIEW MORE
story-1
Top 6 Best Deals Available on New Fords & Lincolns Right Now

Some great targets in today's expensive world.

By Brett Foote | 2026-06-15 09:35:19


VIEW MORE
story-2
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-3
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-4
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-5
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-6
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-7
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-8
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-9
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE