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

How To Control TCC Lock Up

Thread Tools
 
Search this Thread
 
Old Aug 5, 2007 | 09:30 PM
  #31  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
Originally Posted by Skandocious
So let me get something straight here... A switch on this wire disables the TC from disengaging when you let off the throttle so it rides the gear down like a manual transmission would? The transmission can still shift gears right?
It can depending on what you are doing with the switch. Are you opening the wire or grounding the wire?
 
Reply
Old Aug 5, 2007 | 10:09 PM
  #32  
Skandocious's Avatar
Skandocious
Postmaster
Joined: Oct 2006
Posts: 4,816
Likes: 1
From: Davis & Newcastle, CA
It can depending on what you are doing with the switch. Are you opening the wire or grounding the wire?
I'm not sure... I'm just trying to understand the point of this other than for diagnostic purposes... Whats the difference between those two Bill?
 
Reply
Old Aug 5, 2007 | 10:43 PM
  #33  
mattyg's Avatar
mattyg
Freshman User
Joined: Jul 2007
Posts: 27
Likes: 0
From: victoria
Could you put an inline slice on the pk/y wire and run it to a switch then to ground

when switch is on tc is locked up
when switch is off tc operates normally

does this make sense??
 
Reply
Old Aug 5, 2007 | 10:48 PM
  #34  
Skandocious's Avatar
Skandocious
Postmaster
Joined: Oct 2006
Posts: 4,816
Likes: 1
From: Davis & Newcastle, CA
Originally Posted by mattyg
Could you put an inline slice on the pk/y wire and run it to a switch then to ground

when switch is on tc is locked up
when switch is off tc operates normally

does this make sense??
That's kind of what I was looking to do...
 
Reply
Old Aug 6, 2007 | 05:21 AM
  #35  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
Originally Posted by Skandocious
I'm not sure... I'm just trying to understand the point of this other than for diagnostic purposes... Whats the difference between those two Bill?
I did it for diagnostic purposes.
The wire color is Purple with a Yellow stripe (P/Y).
If the wire is grounded the TC clutch is on.
If the wire is open at the transmission the TC clutch is off.
If the TC clutch is on the engine is locked to the transmission as if you do not have a TC and the engine will die if you come to a stop (not tested).
Normally the TC clutch does not lock the engine to the transmission until you reach 43 MPH.
 
Reply
Old Aug 6, 2007 | 06:43 AM
  #36  
netscaner's Avatar
netscaner
Elder User
Joined: May 2007
Posts: 754
Likes: 1
From: Solon, Ohio
Originally Posted by subford
Normally the TC clutch does not lock the engine to the transmission until you reach 43 MPH.
I have one of those 4r70w transmissions that shifts hard from first to second and was thinking of trying this to help soften it while doing around town driving.

I guess if it doesn't kick in till 43 mph this would be a waist of time.

Is it possible mine kicks in too early ??
 
Reply
Old Aug 6, 2007 | 07:51 AM
  #37  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
Originally Posted by netscaner
I have one of those 4r70w transmissions that shifts hard from first to second and was thinking of trying this to help soften it while doing around town driving.

I guess if it doesn't kick in till 43 mph this would be a waist of time.

Is it possible mine kicks in too early ??
The 1-2 shift happens at about 10-20 MPH so yes it would be a waist of time.
You might want to check your TPS as this is the pressure sensor for the transmission. If you have high pressure then you would have hard shifts or maybe some body before you put a mod in the valve body.
A hard shifting transmission will last long than a soft shifting transmission.
 
Reply
Old Aug 6, 2007 | 08:19 AM
  #38  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
If you are thinking of making a tester here are the diagrams of the one I made for the 4R70W.

http://i54.photobucket.com/albums/g9...sion/view3.jpg

http://i54.photobucket.com/albums/g9...sterWiring.jpg
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

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

 Verdad Gallardo
story-1

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-2

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote
story-3

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-4

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-5

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-6

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-7

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-8

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-9

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
Old Aug 6, 2007 | 08:47 AM
  #39  
netscaner's Avatar
netscaner
Elder User
Joined: May 2007
Posts: 754
Likes: 1
From: Solon, Ohio
Wow........
Thanks again Sub
 
Reply
Old Aug 6, 2007 | 08:59 PM
  #40  
Skandocious's Avatar
Skandocious
Postmaster
Joined: Oct 2006
Posts: 4,816
Likes: 1
From: Davis & Newcastle, CA
One quick question Bill. I'm about to install a TCC clutch disable switch and I think I might have bought the wrong thing. I wanted to get a switch with an LED so if it got bumped it would shine in my face to let me know, but I think the light is going to shine during the wrong time...

The light shines when the circuit is closed. When I flip the switch down (turn the light off) it breakes the circuit. I didn't really understand your post so can you explain again; if the circuit is closed (light on) then the TC clutch is going to act normal as if I had never installed the switch, and if the circuit is broken (light off) then it is going to lock the TC to the engine? Is there a way for me to swap these so that the light comes on when I LOCK the TC? Here's the switch that I bought:

http://www.partsamerica.com/ProductD...rtNumber=84841

Has three prongs on the back:

--- +12v
----- load
--- ground

Any help is appreciated.
 
Reply
Old Aug 6, 2007 | 11:30 PM
  #41  
Skandocious's Avatar
Skandocious
Postmaster
Joined: Oct 2006
Posts: 4,816
Likes: 1
From: Davis & Newcastle, CA
Okay I just installed this switch and it really messed up my truck. The disconnected position just made the shifts really soft and weird... it did not ride the gears down nor did it stall at a red light. Switched it back to on and now my truck shifts WAY MESSED UP!!

Also threw 122 code when I switched it to off:

TPS circuit below minimum 0.6 volts.

WTF?!
 
Reply
Old Aug 7, 2007 | 12:05 AM
  #42  
Skandocious's Avatar
Skandocious
Postmaster
Joined: Oct 2006
Posts: 4,816
Likes: 1
From: Davis & Newcastle, CA
Well I'm pretty sure that I spliced into the TPS wire instead of the TCC wire. The diagram that subford posted was backwards from what you can see when you look at the harness in the engine compartment. So I finally got it spliced back together... Hopefully she'll stay... Now I'm resetting the computer and I'll take it for a drive in a few minutes... Any chance I might have caused some damage?
 
Reply
Old Aug 7, 2007 | 01:14 AM
  #43  
Skandocious's Avatar
Skandocious
Postmaster
Joined: Oct 2006
Posts: 4,816
Likes: 1
From: Davis & Newcastle, CA
Spliced the connection back together and reset the computer. Truck runs fine now. Phew!! Scared me... I still kind of want to do the TCC mod but I don't want to deal with any more of those wires on the EEC, especially not that my TPS wire is so short, I don't want to risk pulling the connector or else I'll have to replace the harness. Can I tap the P/Y wire on the E4OD plug in the top right of this pic:



What is that plug called and where is it located?
 
Reply
Old Aug 7, 2007 | 10:19 AM
  #44  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
Originally Posted by Skandocious
Here's the switch that I bought:
Has three prongs on the back:

--- +12v
----- load
--- ground
I take this is the switch you bought.

No the LED will not work the way you wanted it to.
The only +12 Power is inside the transmission and you are either grounding it or not.
Originally Posted by Skandocious
The diagram that subford posted was backwards from what you can see when you look at the harness in the engine compartment.
The diagram was of the Computer Plug. The Computer Plug harness would be a mirror image and you were also one pin off.
Why were you at the computer plug anyway?
The Transmission harness does not have the TPS wire in it. This is the harness you should have been working with.

The plug you want is on the driver’s fender.
 
Reply
Old Aug 7, 2007 | 10:39 AM
  #45  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
Originally Posted by Skandocious
What is that plug called and where is it located?
It is called C103 and it is not in any of the diagrams you posted.
It is on the frnder under the Master Cyl.
 
Reply



All times are GMT -5. The time now is 07:43 PM.

story-0
Rezvani's Latest Post-Apocalytic 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 | 2026-05-30 18:33:59


VIEW MORE
story-1
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-2
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-3
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-4
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-5
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-6
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-7
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-8
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-9
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE