vehicle speed sensor
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vehicle speed sensor
My 1994 full size Bronco with an E40D trans is throwing codes of 452 and 542. The first one has to do with the VSS and the second indicates an open circuit at the fuel pump. Where is the VSS and could this be causing hard shifts at high rpms? Seems to only do this when the engine is warm. Any help is appreciated.
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From: Corona, CA
vehicle speed sensor
Yipper dipper, on the shifting part. The VSS (Vehicle Speed Sensor) is a sensor on top of the rear differential that detects how fast your going. This with the PSOM (Your spedo) tells your tranny how fast your going so it can make good shifts when it needs to.
The first thing I would check is the wire going to the VSS which will be on the top of the diff. Sometimes they get unplugged and have been known to be sheared off completely at times.
But with the Fuel pump open circut problem I would take a hard look at your wiring harness to see if it has been damaged or burned through by something.
The first thing I would check is the wire going to the VSS which will be on the top of the diff. Sometimes they get unplugged and have been known to be sheared off completely at times.
But with the Fuel pump open circut problem I would take a hard look at your wiring harness to see if it has been damaged or burned through by something.
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Joined: Sep 2002
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From: Gateway to the West
vehicle speed sensor
Could be a filthy VSS. Its held in by one bolt and is easily wiped clean and reinstalled. If its an heat related problem, you could be dealing with connections that aren't quite as tight as they need to be and the heat expansion causes poor conductivity. After all the sensor is mounted at the TOP of the rear diff. housing and heat rises.
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vehicle speed sensor
I've been pulling intermittent 452 codes on my 94 5.0L for a while now. I've also been having intermittent shifting problemns with the transmission (E4OD) - harsh upshifts, sluggish acceleration, slipping out of gear. The two may be connected.
My local Ford shop first replaced the speed sensor on the rear diff. but this didn't fix it. Then then said they had detected a fault in the ABS module (the signal from the sensor is routed through the ABS module on its way to the PSOM) and replaced that at considerable expense! That didn't fix the problem either. It's now back in the shop and they are looking at it again.
The problem is intermittent but never seems to occur in the morining. It usually manifests itself on the way home from work in the afternoon. Leave it overnight and it's fine again the next day.
My local Ford shop first replaced the speed sensor on the rear diff. but this didn't fix it. Then then said they had detected a fault in the ABS module (the signal from the sensor is routed through the ABS module on its way to the PSOM) and replaced that at considerable expense! That didn't fix the problem either. It's now back in the shop and they are looking at it again.
The problem is intermittent but never seems to occur in the morining. It usually manifests itself on the way home from work in the afternoon. Leave it overnight and it's fine again the next day.
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vehicle speed sensor
Your problem with the transmission sounds exactly like mine. It is intermittent and seems to occur when the transmission and/or the weather is hot. When started in the morning it works fine but after driving some distance it begins to act up. The problem must be electrical though I suppose some type of valve could act up after getting warm. Just replaced the VSS sensor though given your luck I'm thinking this won't solve my problem. Let me know how you make out at the dealer.
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From: Corona, CA
vehicle speed sensor
Sounds like you guys have bad shift selector switches on your tranny. A couple years back I had the same symptoms and took my truck in thinking the tranny was toast. Lucklly the tranny shop my family has been using for 20 some years is still quite honest and by doing a couple of external tests found I had a faulty Shift selector switch. He also told me that these commonly went out on the E4ODs and ford had an updated version. 150 bucks later (120 for the part 30 for the labor) I was back on the road happy not to have spent 1600 bucks for a tranny I didn't need.
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vehicle speed sensor
One of the first things I did was have the MLPS (manual lever position sensor) changed out - I assume were taking about the same thing. Unfortunately it didn't fix the problem.
I've just picked up my Brono from the shop. This time they replaced the PSOM (programable speedometer/odometer module) - they replaced the entire instrument cluster. It's too early to say whether it's fixed it or not - I need to drive it around a bit. Fingers crossed.
I've just picked up my Brono from the shop. This time they replaced the PSOM (programable speedometer/odometer module) - they replaced the entire instrument cluster. It's too early to say whether it's fixed it or not - I need to drive it around a bit. Fingers crossed.
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vehicle speed sensor
Replaced the VSS but the trans still doing the same thing. What kind of costs are involved with replacing the PSOM? Wonder if you can pick one up from the junk yard.
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vehicle speed sensor
I'm sure you could pick one up at a junk yard. The invoice from the ford dealership had the replacement PSOM at $375 plus 2.5hrs labor. I've read threads on this forum about doing the replacement yourself and how to set the mileage on the odometer etc. Just do a search for PSOM
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