Please HELP!!
1996 F150 2WD Ext cab 5.0 engine with auto trans.
Was driving around today everything was fine all gauges and dash working. Then started smelling something like wires burning. Went into store and came out several hours later. Truck cranked fine but speedometer was not working and odometer was blank (no readout). Found #16 (scan port) and #18 (speedometer) fuses blown. Had a parts store read codes found P0500 speed sensor A. Then P0401 and P0402 which have been up forever something to do with EGR. So I replaced both fuses and pulled the connector off the speed sensor at the rear end. Then cranked truck. Odometer flashed on then both fuses blew again and the ABS light was on as would be expected. The only thing I can think of left would be the PSOM. I took the instrument panel out this afternoon and found no burnt or melted wires. Everything else works as normal. All lights, radio, everything that I can think of. Have not tried blower motor or cruise.
Sorry to be long winded but wanted t get all details out there. I know some of you got to have seen this and look forward to your help.

 

Did you check all the wiring to the speed sensor ?

 

Most of it. Figured the problem was in the dash since I was able to smell it

 

Sounds like wires shorting out. If it is the PSOM that one is specific - 96 is the only one that will work because of the change to OBDII. 97 250 or 350 ones might work, not sure on that.
I have one from a 96, but it's no good to you - Canadian truck, so it's in kilometers instead of miles.

 

ok found issue with #16 the scan port and lighter are on the same circuit found a penny in the lighter socket. now I just have the 1 major issue

 

Got it. Found a thread on Fordf150. it was the Air bag Module. Took it out and could smell the burn. I unhooked all 3 things on that circuit which was the shift lock. PSOM, and air bag. Plugged them back in until the only thing left was the air bag. Pulled the light so I would not have to look at it. Maybe this will help somebody out in the future