Topic Sponsor
2004 - 2008 Ford F150 General discussion on the 2004 - 2008 Ford F150 truck.

trans temp factory wire?

Thread Tools
 
Search this Thread
 
Old Sep 29, 2009 | 05:09 AM
  #1  
blackbetty's Avatar
Thread Starter
Paint it black
 
Joined: Oct 2007
Posts: 2,667
Likes: 20
From: washington dc
Default trans temp factory wire?

rumor has it that the factory obd2 has a wire for the in pan temp that you can tap into to use for a external gauge. anyone have some alldata or a diffrent wiring diagram what would like to shed some light on this and maybe provide the wire?
Reply
Old Sep 29, 2009 | 06:35 AM
  #2  
Mod (Ret.)'s Avatar
Moderator (Ret.)
Supporting Member

 
Joined: Sep 2008
Posts: 9,460
Likes: 486
From: Lake Mary Florida
Default

I'll check my 2005 Ford factory wiring book tonight. I can confirm that there is a lead in the OBD II plug, as my SCANGUAGE II displays the transmission temp, and it plugs into the OBD II port.
Reply
Old Sep 29, 2009 | 01:48 PM
  #3  
blackbetty's Avatar
Thread Starter
Paint it black
 
Joined: Oct 2007
Posts: 2,667
Likes: 20
From: washington dc
Default

i cant pull it up on my sct, because the live wire was a near 700 dollar piece of crap, however let me know because i realy dont want to put a bung in my pan and i dont feel like buying a new pan yet.
Reply
Old Sep 29, 2009 | 04:19 PM
  #4  
thump's Avatar
Senior Member
 
Joined: Jul 2009
Posts: 688
Likes: 17
From: CO
Default

Originally Posted by Bucko
I'll check my 2005 Ford factory wiring book tonight. I can confirm that there is a lead in the OBD II plug, as my SCANGUAGE II displays the transmission temp, and it plugs into the OBD II port.
Interesting.... subscribed.
Reply
Old Sep 30, 2009 | 04:51 PM
  #5  
blackbetty's Avatar
Thread Starter
Paint it black
 
Joined: Oct 2007
Posts: 2,667
Likes: 20
From: washington dc
Default

bump
Reply
Old Oct 1, 2009 | 07:12 AM
  #6  
Mod (Ret.)'s Avatar
Moderator (Ret.)
Supporting Member

 
Joined: Sep 2008
Posts: 9,460
Likes: 486
From: Lake Mary Florida
Default

I forgot to do this last (Wednesday) night. I promise to look at the Ford schematics tonight to see if they point out a single lead on the OBD II plug.

On my SCANGUAGE II, I did have to program (using XGUAGE inputs) this to display on the gauge, as not all manufacturers provide this reading. This makes me think that it is not a dedicated lead, but since I'm not sure, I will read the schematics tonight and report back.
Reply
Old Oct 1, 2009 | 12:01 PM
  #7  
Keeblerz28's Avatar
Senior Member
 
Joined: Jul 2009
Posts: 444
Likes: 2
From: Iowa
Default

I don't believe that there is a single wire you can tap to mount a tranny temp gauge. The OBDII port is a digital interface, so you need a device that can interface to read the data. FWIW, my Edge Evo can pull up my tranny temp.

http://en.wikipedia.org/wiki/On-boar...nostics#OBD-II
Reply
Old Oct 1, 2009 | 12:45 PM
  #8  
Mod (Ret.)'s Avatar
Moderator (Ret.)
Supporting Member

 
Joined: Sep 2008
Posts: 9,460
Likes: 486
From: Lake Mary Florida
Default

There may be....It took me awhile to trace this on the Ford schematics, as they (Ford) refer to the OBD II as a "Data Link Connector" (DLC). Pins 6 and 14 (CAN H and CAN L) of the DLC connect to the Powertrain Control Module (PCM) located in the engine firewall, passenger side on pins 2 and 3 ("output pins"). The PCN gets the Transmission Fluid Temperature (TFT) from input pin 20 of the PCM; this is an orange/black wire. This Orange/Black wire comes from a connector at the top of transmission, behind torque converter/bell housing. It is pin 5 of a 10 pin connector.

What I cannot say for 100% certainty is if this one wire lead is indeed a voltage type sensor. In other words, it can be connected to a simple farieheit guage, and give a simple temperature reading. The Ford schematic does say that pin 5 of the transmission plug is a "transmission Fluid Temperature (TFT) sensor" though.

My SCANGUAGE II plugs into the OBD II (A.K.A DLC), and reads the TFT via pins 6 and 14. The SCANGUAGE required programming to read from these pins, as they represent a "BUS", meaning several items are reported on these two pins. SCANGUAGE requires a TRANSMIT and RECIEVE address, specific to the TFT sensor. I would not tap off these pins to get one specific reading, unless you have a device like the SCANGUAGE that allows you to enter the specific TRANSMIT/RECEIVE address.

I suggest that pin 20 of the PCM or pin 5 of the transmission connector be used for the test using a conventional transmission temp guage. Both are the ORANGE/BLACK 20 guage wire.

Good luck, and let us know if it works.

Last edited by Mod (Ret.); Oct 1, 2009 at 12:56 PM.
Reply
Old Oct 1, 2009 | 01:20 PM
  #9  
blackbetty's Avatar
Thread Starter
Paint it black
 
Joined: Oct 2007
Posts: 2,667
Likes: 20
From: washington dc
Default

well...gulp...i will crack it open next week sometime, or maybe saturday...thanks for the info bucko, i will indeed post my findings
Reply
Old Oct 1, 2009 | 01:25 PM
  #10  
Keeblerz28's Avatar
Senior Member
 
Joined: Jul 2009
Posts: 444
Likes: 2
From: Iowa
Default

Oh good point Bucko, I meant to say I don't think there's a single wire in the OBDII port that will give you analog transmission temperature. You may be on to something, being able to tap a wire that feeds this information from the tranny to the PCM
Reply



All times are GMT -4. The time now is 09:26 AM.