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Discussion Starter #1
I'm getting a random hard shifting issue. It almost seems like sharp turns will sometimes trigger it. It will be a hard shift through all gears but will go away if I turn it off and restart it so I assume it's an electrical issue. Sometime the OD light flashes and sometimes it doesn't when it happens. A couple weeks ago it did it close to home and I was able to pull codes at my neighbors prior to turning it off while the OD light was flashing. Codes were P1351,1359,0401,0500. 0500 relate to the VSS so I change it out with no luck. Tonight it did it again about 5 miles from the office. I pulled over, turned it off and back on and it was fine the other 25 miles home. What should I try next?
 

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1978 Bronco Ranger XLT, 400/C6 92 K documented miles &1994 Bronco,XLT 85K original miles
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What year and transmission??
 

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It's the psom. Very common problem. Disconnect the shift indicator wire from the gear shift lever. Unscrew the small black screw holding the plastic piece on. Remove the lower dash trim and the cluster bezel. Turn the key on, shift to 1st gear and lower the tilt wheel all the way. Remove the 2 screws holding the cluster bezel on. Then pull it forward, disconnect the rear window switch and the 4 wheel drive switch. Then remove the bezel. Next unscrew the screws holding the cluster to the dash in the 4 corners. Pull the bottom edge of the cluster forward enough to reach behind it and disconnect the 3 wiring connectors. Then Pull out the cluster bottomfirst to clear the dash opening, remove the clear plastic shield then pull each gauge section out. You can gently pry them out around the edges with a flat head screwdriver. Then remove the 2 screws holding the gear shift indicator to the speedometer. Remove the speedometer. From here you have 2 options. You can send it up to modulemechanics.com for repair for $89. Or you can buy a replacement psom from ebay. From my experience, the lower the mileage the more likely it's still working. But remember you will still need to repair that one one day.

I would suggest trying the repair route first. It doesn't always work because the integrated circuits go bad too eventually and they are not repairable, but most of the time it's the capacitors or a diode or just weak old solder joints that are making it malfunctioning. If that doesn't work then you can look for a replacement on ebay.
 

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Discussion Starter #4
It's the psom. Very common problem. Disconnect the shift indicator wire from the gear shift lever. Unscrew the small black screw holding the plastic piece on. Remove the lower dash trim and the cluster bezel. Turn the key on, shift to 1st gear and lower the tilt wheel all the way. Remove the 2 screws holding the cluster bezel on. Then pull it forward, disconnect the rear window switch and the 4 wheel drive switch. Then remove the bezel. Next unscrew the screws holding the cluster to the dash in the 4 corners. Pull the bottom edge of the cluster forward enough to reach behind it and disconnect the 3 wiring connectors. Then Pull out the cluster bottomfirst to clear the dash opening, remove the clear plastic shield then pull each gauge section out. You can gently pry them out around the edges with a flat head screwdriver. Then remove the 2 screws holding the gear shift indicator to the speedometer. Remove the speedometer. From here you have 2 options. You can send it up to modulemechanics.com for repair for $89. Or you can buy a replacement psom from ebay. From my experience, the lower the mileage the more likely it's still working. But remember you will still need to repair that one one day.

I would suggest trying the repair route first. It doesn't always work because the integrated circuits go bad too eventually and they are not repairable, but most of the time it's the capacitors or a diode or just weak old solder joints that are making it malfunctioning. If that doesn't work then you can look for a replacement on ebay.
Thanks for all the detailed info! After seeing this I search PSOM and see a lot more info than I was finding before.
 
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