I recently purchased a 1995 Ford F150 4X4. It has a Trouble Code of 636- Transmission Oil Temperature sensor voltage out of test range. The person I bought it from did replace the transmission right before I bought it. So, I am assuming (which I know that assume means...*** out of u and me, but I am assuming that it is safe to assume, LOL) that he may have left the TOT disconnected. My truck has the 4R70W (AODE) transmission. Can someone please tell me where the TOT sensor is located?

 

Truck and trans up to full running temp before running KOEO and or KOER tests?

If not will result in 636 TOT sensor voltage out of self test range.

If was up to temp check and not reason for code, check the sensor for proper value for any given temp.

All temps given in "F",

32deg - 58deg = 37 - 100k
58 - 104 = 16 - 37k
105 - 158 = 5 - 16k
195 - 230 = 2.7 - 5k
195 - 230 = 1.5 - 2.7K
231 - 266 = 0.8 - 1.5K
267 - 302 = 0.54K - 0.8K

And of course check circuit between the pcm and trans, make sure that wire shows continuity, IE that it is not damaged/broken at some point in between the two.

 

Yup, TOT sensor is in the transmission oil pan near the valve body. You know what year the new trans is? On 98 and newer transmissions, it's integrated into the black plastic circuit assembly. You'll see what I mean when you get in there... and on transmissions older than 98 I don't remember "exactly" where it is but it's still in the pan somewhere.

That all applies to the 4R70W. An AODE will be the same. Although they AIN'T the same transmission exactly... the 4R is basically an AODE with a wide-ratio gearset. That's what the W is for in 4R70W.

EDIT: danr1 beat me to it... and provided a picture too. Thanks danr1.

 

Okay, now, another slightly different subject (still diagnostic codes). When I first got the truck, it had a fast idle. Without reading a repair manual, I made an adjustment to the idle screw, on top of the throttle body (I guess that is what it is called. The part that the IAC is bolted to.). When the engine died, and would not restart, I decided that it might be a good idea to read the repair manual. Too late, it said to make no adjustments to that screw. Then why is the screw there? So, I made some more adjustments to it (what choice did I have?), and got it to start back up again. The idle is lower, but, it has a little bit of an eratic idle, and I have a code 122, TP sensor circuit below minimum voltage. Not sure if that has anything to do with that screw.

 

It well might.

Under normal conditions the PCM opens and closes the IAC to adjust the vehicle's idle speed. In your vehicle, conditions are no longer normal. By backing the stop screw out you have closed the throttles tighter, resulting in the TPS voltage being less than specified. Your IAC is also working overtime to keep the idle speed where it needs to be, which is not a real problem until the engine needs to idle up and there isn't enough IAC left to do it.

What you'll need to do is pull the SPOUT from the harness and set timing to spec (probably 10 degrees BTDC, unless your VECI label says different) then disconnect the IAC and carefully adjust that stop screw to specified idle speed -- if memory serves it's 675 + or - 50 RPM, but check with another source before you depend on my memory. Verify that the TPS_Signal is between 0.6 and 1.0 volts as measured against SIG_RTN. Put everything back together, clear codes (easiest done by turning off your OBDI code reader in the middle of a read), drive the vehicle for a spell, then check to see if the codes came back.

 

Bah, I've adjusted that screw on almost all my Fords for one reason or another. All it is, is a stop for the throttle arm, as you can see. Probably to keep the blade from wearing on the bore when at idle. IIRC there is a procedure to set it but what I do is unplug the IAC valve and adjust the idle to where I like it, around 675 RPM hot. Then plug the IAC back in and let the computer do it's thing. That way I'll always have minimum idle if I ever unplug the IAC (or it fails or whatever).

EDIT: Damn, beat by someone AGAIN tonight... LOL. Ok well broke vet got you covered then. And lol at the specified RPM... that happens to be right where I like it to idle without IAC.

 

Hindsight being 20 20 and all that jazz, not first one leap in without reading instructions! but anyway yea shouldn't have messed with that screw. It's a throttle stop screw adjusted at the factory locked/sealed in place never requires further adjustment beyond that point.

It prevents the butterfly plates from digging into the throttle body.

You need to put that screw back to the exact position it was in originally provided no one turned it before you did, maybe get lucky use what left of the factory seal that is on em to return it where it was to start with.

And yes you backed the screw out to reduce actual idle speed, doing so certainly could result in TP sensor circuit below minimum voltage.

Minimum voltage = 0.6 volts, acceptable fully closed value = 0.6 to 1.0 volts.

TPS mounted to throttle body any reading between 0.6-1.0 volts is perfect.

Regroup see if you can easily return it to where it was before you moved it, recalling number of turns you made or by using what's left of factory sealant or both to do it.

Then return here for help figure out what the real cause of the problem is, could be vac leak could be faulty TPS etc but its not that screw not if it was in its factory position before you turn it.

Third!!?? WOW do I type slow.........