blackbetty

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?

Mod (Ret.)

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.

blackbetty

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.

thump

Interesting.... subscribed.

blackbetty

bump

Mod (Ret.)

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.

Keeblerz28

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

Mod (Ret.)

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.

blackbetty

well...gulp...i will crack it open next week sometime, or maybe saturday...thanks for the info bucko, i will indeed post my findings

Keeblerz28

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