E40D hard shift in every gear
 

My 1996 F150 gives a 0500 code. plus fuse #18 in mini panel on drivers side dash blows. I'm trying to find the transmission control module. but my Ford repair manual is not very clear on where it or it's conn are located! Any and all help is welcome and appreciated!!!

The transmission is controlled by the Powertrain Control Module (PCM). This computer controls the engine and the electronic controlled transmission in your truck.

The root cause for your P0500 code is the blown Fuse 18. It supplies power to the PSOM, which in turn provides a usabe Vehicle Speed Sensor (VSS) signal to the PCM.

Fuse 18 supplies power to the PSOM, Electronic 4x4 shift control, Air Bag Diagnostic Module and the Shift Interlock (prevents the shifter from coming out of park unless your foot is on the brake).

Hi from Arcadia! Also check fuse #8 too. That fuse goes to the the dome light and the dome light has been known to blow that fuse.

As for fuse #18, does it blow as soon as you plug a new one in or after turning the key on?

Live and Learn!!!
 

After studying the shop manual, (DUH)! I learned that the TCM only applies to 4wd!!!! SO--- on to more trouble shooting.
1) Short has been fixed. Have a bad Airbag Diagnostic Monitor mod. Internal cap is dead short.
2) Have Batt volt to PSOM.
3) Have Run volt ts PSoM.
4) Have correct mi indicated on odometer.
5) ALL lights, gauges work properly.
6) I have no way measure VSS.
7) Truck starts, shifts from park to any gear. (No ADM installed, instrument cluster uninstalled)
I may have given more info than needed, but it gets rid of a mild case of FRUSTRATION!!!!
All this to say, how do I know if the PSOM is A.O.K. and what's next?

If you have a Digital Voltmeter you can measure the VSS signal:

CHECK SPEED INPUT SIGNAL

NOTE: Only wiring harness end of connector is to be probed.
* Connect Rotunda Digital Volt-Ohmmeter 014-00407 or equivalent to Pin 4 (speed in ) and Pin 5 (speed in -).
* Does the voltage increase smoothly and continuously from 0 to approximately 3.5 volts as vehicle speed increases from 0 to 48 km/h (0 to 30 mph)?
OR:
* If available, a frequency counter may be connected to Pin 4 (Speed in ) and Pin 5 (Speed in -).
* Does the displayed frequency of the signal increase smoothly and continuously from 0 to approximately 667 Hz at approximately 48 km/h (30 mph)?
OR:
* If neither a voltmeter nor frequency counter is available, vehicle speed control may be used as a good indicator. If it works normally, then the speedometer module is at least receiving a speed input signal and the wiring and sensor can be assumed to be good.

Rear axle sensor should read 800-1400 Ohms across the pins, and more than 10 Ohms from the metal shell to either pin.

Some good information from Steve83 here: http://www.supermotors.net/registry/media/95932

Test Complete
 

I did as you instructed and the voltage did as you said! Used an ancient Simpson 260 to measure.
I'l be buying both a ADM mod and a PSOM.
I'll poston repair results.
Score another one for this sight's members!!!
Many thanks!

Before spending some coin on a PSOM pull yours out then inspect for signs of broken or loose components as well as the ever prevalent leaking capacitors. You might get lucky with a simple fix.

And hello from North Port!

I just wanted to clarify something... are you having the hard shifts with the instrument cluster removed? If so that is the reason. The PSOM is on the back of the cluster, and is needed to supply the PCM with usable speed data. Without it you will get hard shifts.

2X on what Dixie460 said on the PSOM not hooked up.

Also the alternator will not charge with out the cluster hooked up properly too!!


Please reinstall the PSOM and cluster to further check things.

yeah i think he knows this.he can't plug it in right now because it keeps blowing the fuse.he's got to fix or replace it and should be good to go.

Update
 

To update my post----- I found the root problem and fixed it!
I'll make it short as I can. It was a bad ORIGINAL connector on diff that was giving good readings at all the wrong times!!!!! But, somewhere along the way, the PSOM failed. Replaced conn. and PSOM and all is well(esp my good old truck). MUST: use dielectric grease on ALL electrical connectors!!!!!
The short blowing fuse #18 was for the airbag diagnostic module and some other functions. Removed bad ADM and found internal cap shorted--I,ll replace it soon.
Then to top it all off, my A/C would not switch to MAX AIR. Replaced several vacuum line conn and one more problem solved! Once again- thanks to all members for their input!!!!!!

Like to see pic of this if you can.

good update and sounds like your solving a few bugs all at once.

Like to see pic of this if you can.
__________________what would you like pics of?