I've got a '92 f150, and I'm trying to reprogram the speedometer, but I can't for the life of me find this light blue/yellow wire.

First, the instructions say "just below the instrument panel" "behind the center of the glove box". So, which one? Or am I using different terminology? My understaning of the glove box is the box on the passenger's side of the truck dash that I put all my junk in, where the instrument panel is on the driver's side...

Still, I looked under both, and couldn't find the connector. I found several one-wire connectors -black/red, black/orange, both under passenger's side, a few under driver's side as well, and lots of multi-wire, but nothing at all anything close to light-blue/yellow. In fact, the only wire I could find at all that was anything close is a blue/yellow wire in the fuel tank switch (which I'm pretty sure won't be it).

At this point I've pretty well disassembled the entire dash looking for this wire. Is there a different color it might be, or a different place I might find it? Or if it's simpler, could I use some wire on the back of the instrument panel?

Any help would be much appreciated

 

I don't believe the 92 F150 is electronic. I think it still is gear driven off a cable connected to the trans.

 

Yes, it is electronic. The wire is just not lb/y - it's actually black & orange. The rest of the instructions worked fine, and my speedometer is recalibrated... I just took a multimeter and probed each of the wires in the 12-pin (only 7 wires there, though) harness on the back of the guage cluster, eliminated all that had any voltage or ground with the cluster disconnected (leaving 2 wires), and took a shot in the dark on the others. Luckily, I got it first try.
Not sure why it's a different color, but oh well.

 

92 is electronic.

here is procedure:

To set the calibration, ground the single wire connector under the glove box it says PSOM (Programable Speedometer Opdometer Module). ”Yes there is only one and it has a spade type plug on the end". I used a wire with clips on both ends to ground the plug to a screw under the dash or try a test light and use the clip end to the PSOM and the other jam in a dooe hinge. Now look at your speedometer on the face of your dash while sitting in the drivers seat and there should be a "reset" button and a "select" button. While holding the reset button in on the trip meter, turn the ignition to 'on' while the wire is still grounded. Let go of the reset button. The speedometer display will sweep once and will show a code of some kind then push in again the "reset" button and the existing code will be displayed with RECAL?, mine said 976 RECAL? Now you enter your new code you came up with by dividing the rolling measurement by PI or 3.14 by pushing the "select" button until it gets to the new calibration code number. You may have to push “select” a whole bunch of times until you get to your code. If you turn off the key at this point the original code will not be changed or any of the 6 lives will not be used. To store your new code press “Reset”. Turn off the key. Unplug the ground wire. To check the new calibration, use the mile markers on the interstate. Run an indicated 60 mph and it should take exactly 60 seconds to go 1 mile.

 

Does this procedure work for the E40d tranny as well?? I have 3.08's in my truck now with 3.73s begging to be installed, but i was waiting to instal until i could figure out how to reset speedo. Thanks in advance, Ben
Btw, i have a 2wd 94 f-150 with 300 and e40d.

 

My understaning (not 100% sure on this) is that the sensor is in the rear end and works on ring gear rotation - i that's true, it shouldn't matter what rear or tranny you have, only tire size would matter. BUT I'm not 100% certain on that

 

go here for more info:

https://www.ford-trucks.com/article/...ND_BRONCO.html