My brother has a 95 Bronco 351 with an E4OD and it ran great until he took the top off two days ago now the speedo is dead and it up shifts really hard into second and I don't have the nerve to see if it will ever make the 2-3 shift. We put a new VSS/ABS sensor in it with no change. Does the the ring on the ring grear for the speed sensor ever go bad (we cleaned it yesterday)? I have checked the wiring and it looks good so the only other think I can think of would be the PSOM, does any one know where you can get one of these and how to check one, and could taking the top off cause this some how because every thing was perfect before he took it off then all this? He has taken the top off many time and this never happened before. Thanks for any help.
-Johnboy

 

I don't think taking your top off had anything to do with the speedo going dead. I would say that the best place to get a PSOM is a salvage yard. My PSOM went bad in ym 1995 Bronco a couple months ago and the dealers wanted around $300 for a new instrument cluster. The PSOM is part of the cluster. I picked one up in the junkyard for $30 and it works great. The only real way to test if it works to with a scan tool. I don't quite remember how but what i do remember is you have to select your VSS and your PSOM if pretty sure and if your VSS reads 0 when your driving around your PSOM is bad. This is becase your PSOM reads the signal from your VSS and relays it to your computer and then back to your tranny and back around again in a loop. If your PSOM is bad your truck will slam shift and most of the time not even want to shift at all. The OD light would be blinking too and a shift also. Good luck buddy.

 

if the od light is blinking there is another issue related to the mlps. if the od light functions as normal but the speedo doesnt work and there rear sensor has been replaced then the psom would be the next step. I also have this same issue. speedo doesnt work, abs light is on and tranny shifts hard. If you decided to tackle this take pics and see about doing a write up. i would be most interested. keep us posted please

 

Thanks for the help the OD light does blink so mabey I will try the MLPS but would that have any affect on the speedo?
-Johnboy

 

The MLPS wouldn't have any affect of the speedo. the only function of the MLPS is to tell the tranny what gear your in and relay that info to your computer and sensors so your PCM can tell the tranny when to shift. The MLPS can cause harsh shifting too. I have also had to replace this. It an easy fix if you want to try it but its kinda spendy. I wuld try a junkyard instrument cluster first. That would be alot cheaper and easier than replacing the MLPS.

 

95 did you take pics or do a write up on your cluster swap?

 

No I didn't. I swapped my cluster at around 9pm in the colleges parking lot using only the dome light. It's really easy though.
1. Take off your trim bezel surrounding the cluster.
2. remove the string attaching the shifter to the indicator. Its on the right side of the steering wheel and is bright orange.
3. remove the 4-7mm screws holding the cluster in.
4. Unplug the 3 connectors on the back of the cluster.
5. installation is the reverse.
6. I would check for burnt out bulbs before I put the new one in though.

 

really thats it, man i was getting a bit worked up over nothing sounds like. just some times the easy stuff ends up being a real pain ya know.

 

yeah it does. the hardest part of the whole deal is getting the wiring harness unplugged from the cluster. Those old pastic connectors are hard to get off. Also don't drop any screws because they suck to find.

 

no kidding about the screws. hate that. well i will look into a jy psom and go from there. thnks

 

Well thanks for all the help I am going to try to find a junk yard PSOM and get that replaced hopefully it will fix the darn thing.
-Johnboy

 

It should be relatively easy to find one. I got mine out of a 1995 Bronco with 178,000 miles on it and it works perfectly. The new speedo will work but you will have to live with the odometer reading what it does for mileage because unless you get a new dealer one you can change the readout. That was fine for me because it dropped my mileage from 186,000 down to 178,000 and now my truck actually has 200,000 miles on it. Good luck guys

 

if the psom was disconnected would the tach still work?

 

Good luck on search My local yard only sells whole units.And now they don't buy this old truck . I just sold the last on from my parts trucks or I'd ship you one. .

 

Tach would still work as PSOM plug is connector c252(12 pin conector,7 wires) and tach is in c250 (14 pin con. 13 wires) other con. is c251( 14 pin con. 14 wires)