Ok this might sound dumb but I had a door switch go bad on my 94 /5.8 I removed the fuse so that the dome light would go out that fuse also runs the speedo and tells the trans what to do. I found this while tracing down wiring diagram. It may sound like Im crazy but without the fuse the trans did shift but it wasn't pretty and its some thing easy to look at .
Yo, Exactly; & Ford addresses this in:
TSB 94-09-12 Visor Screws
TSB 95-14-11 Dome Lamp Screws
Publication Date: JULY 17, 1995
LIGHT TRUCK: 1994-95 BRONCO, F SUPER DUTY, F-150-350 SERIES
ISSUE: Some customers may have concerns that the following features are inoperative:
* All courtesy lamps
* Map lamps
* Engine compartment lamp
* Glove compartment lamp
*
Odometer in the instrument cluster
* Dome lamp
* Power mirrors
* Lighted vanity
* Cargo lamp
* Remote keyless entry
This is due to insufficient clearance between the outer roof panel of the cab and a map/dome lamp mounting screw, causing a short in Circuit 54, which causes Fuse 8 (15 amp) to become inoperative. This fuse protects the wiring for the above vehicle features.
ACTION: Replace existing dome mounting screws with new, shorter screws. Refer to the following procedure for service details.
BACKGROUND
Three (3) screws (52814-S36) are required to mount the map/dome lamp to the inner roof panel of the cab. Two (2) of the three (3) screws are used to complete two (2) electrical circuits, 53 and 54. Circuit 53 is after the lamp switches and is "cold" ("cold" means that 12 volts are not present) and Circuit 54 is before the lamp switches and is "hot" at all times ("hot" means that there are always 12 volts present).
The 52814-S36 screw is approximately 25.4mm (1") long. When there is a sufficient amount of downward force applied to the outer roof panel of the cab, the panel will make contact with the screw that has Circuit 54 (12 volts) on it. For example: When the brushes and dryer pass over the roof of the truck in a car wash or when traveling at highway speeds. As the roof panel contacts the screw, it causes a direct short-to-ground. When this occurs, Fuse 8 will be overloaded (15 amp), open and disable the listed features.
SERVICE PROCEDURE
1. Carefully pry pillar/dome lamp lens from interior lamp body.
2. Remove screws retaining interior lamp (map/dome) to roof trim panel.
3. Install new screws (52802-S36, 19mm).
NOTE: ANOTHER OPTION WOULD BE TO REMOVE OLD SCREWS AND CUT/GRIND APPROXIMATELY 6.35mm (1/4") OFF THE END AND REINSTALL.
4. Reinstall pillar/dome lamp lens.
PART NUMBER PART NAME
52802-S36B Screw (19mm)
OTHER APPLICABLE ARTICLES:
95-2-11
WARRANTY STATUS:
Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage
OPERATION DESCRIPTION TIME
951411A Replace Dome Lamp Mounting Screws 0.3 Hr.
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TSB 94-09-12 Visor Screws
Publication Date: MAY 4, 1994
LIGHT TRUCK: 1994 BRONCO, F-150, F-250, F-350
ISSUE: The Instrument Panel Electrical
PSOM (Programmable Speedometer/Odometer Module) may be inoperative or not function properly and the #8 fuse may be blown. In addition, if
the vehicle is equipped with an E4OD transmission, it may exhibit a harsh shift. These conditions may be caused by trim screws installed through the 17K745 visor wire between the left hand "A" pillar and the left hand visor bullet connector.
ACTION: Tape the damaged or exposed wire conductor and add scrolling to protect the wiring from trim screw shorts. Refer to the following service procedures for service details.
SERVICE PROCEDURE
1. Remove the garnish moulding. Refer to the 1994 Econoline, F-150-350, Bronco F-Super Duty Service Manual, Page 01-05A-5, for the removal procedure.
a. Inspect the wiring condition against the trim screws.
b.Check screws for burn marks.
2. If burn mark is found, use electrical tape to protect exposed/damaged wire. Add 1/4" (6.35 mm) scrolling to maximize protection.
3. Replace #8 fuse.
4. Reset the PSOM to see if it is functioning properly. Refer to the 1994 Econoline, F-150-350, Bronco F-Super Duty Service Manual, Page 13-01A-8, for the reset procedure.
5. Reinstall trim. Refer to the 1994 Econoline, F-150-350, Bronco F-Super Duty Service Manual, Page 01-05A-5, for the installation procedure.
6. Recheck fuse #8 and PSOM final verification.
PART NUMBER PART NAME
D4FZ-14A099-B 1/4" Scrolling (25 Ft. Roll)
D6AZ-19627-A Electrical Tape
D9ZZ-14526-D Fuse
OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: Eligible Under The Provisions Of The Bumper To Bumper Warranty Coverage
OPERATION DESCRIPTION TIME
940912A Check And Repair Wiring 0.6 Hr.

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Also; other issues that affect the PSOM are
TSB 95-5-21 Fuse "E" Inoperative - ABS Light On - Back-Up Lamps Inoperative - DRLs Inoperative - MIL On - Speedometer Inoperative
Publication Date: MARCH 13, 1995
LIGHT TRUCK: 1992-1995 BRONCO, F-150-350 SERIES
ISSUE: On some vehicles the HO2S wires in the 12A690 (subassembly of the 14B060 battery cable) harness may become chafed and the vehicle could exhibit any one of the following conditions:
ABS light on
Speedometer inoperative
Back-up lamps inoperative
Daytime running lamps inoperative
Trailer battery charge relay inoperative
MIL on, displaying Codes: 172, 173 or 41 for HO2S failure
Inadvertent PCM Self-Test
ACTION: Replace the damaged wire harness and HO2S sensor. Refer to the following procedure for service details.
SERVICE PROCEDURE:
1. Disconnect negative battery cable.
2. Disconnect the solenoid terminal and positive battery cable from the starter.
3. Pull the cable downward to inspect the 12A690 harness for chafing, pinholes, etc. If necessary, remove the convolute and tape from the 12A690 harness located next to the lower RH side engine mount.
4. If the 12A690 harness is damaged, replace the 14B060 assembly (F5TZ-14300-EA) and the HO2S sensor (F4UZ-9F472-A).
5. Inspect Fuse "E" and replace if necessary (D9ZZ-14526-D).
6. Clear all codes stored in memory.
7. Retest and verify the concern has been resolved.
PART NUMBER - PART NAME
D9ZZ-14526-D Fuse - 15 Amp
F5TZ-14300-EA Harness Assembly
F4UZ-9F472-A HO2S Sensor
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PSOM & Odometer Not Working & E4OD Harsh Shift TSB 94-09-12 for 94 Bronco & F Series; "...PSOM (Programmable Speedometer/Odometer Module) may be inoperative or not function properly and the #8 fuse may be blown. In addition, if the vehicle is equipped with an E4OD transmission, it may exhibit a harsh shift. These conditions may be caused by trim screws installed through the 17K745 visor wire between the left hand "A" pillar and the left hand visor bullet connector..."
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all above by Ford via Steve83
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PSOM Pointer Waiver TSB 96-21-11 for 92-96; "..The speedometer needle may waver and or a light surge may occur on some vehicles...This may be due to slight dents/chips in either the exciter ring or the Vehicle Speed Sensor (VSS) and air gaps between the VSS and the exciter ring. Any slight dents, chips, etc., in either the exciter ring or VSS will create needle waver. Measure air gap between the VSS and exciter ring. It should be 0.38-0.51mm (0.015-0.020"). Check exciter ring runout per the same ring gear backface runout procedure of the appropriate model 1996 Powertrain/Drivetrain Service Manual, Section 05-00. Make sure the exciter ring is mounted correctly to the ring gear. If runout is more than 0.1mm (0.004"), perform the differential runout check per the procedure in the appropriate model 1996 Powertrain/Drivetrain Service Manual, Section 05-02A or 05-02D, to find cause and repair as needed. If all items listed above check good, replace the Instrument Cluster Assembly. Obtain the correct service part number from the Parts Catalogue and then contact the Electronic Odometer Exchange Center at (800) 259-9700 for U.S. Dealers and (800) 663-9974 for Canadian Dealers..."
read more Source: by Ford via miesk5 at cc