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Old Oct 17, 2021 | 11:53 AM
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khaled Alharbi's Avatar
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computer codes

Hi, I checked the computer codes and these codes appeared
F-150 1993 5.0
(654) transmission selector not in PARK -
transmission
------
(452)vehicle speed sensor (VSS) problem
------
(634) Park/Neutral Position (PNP)
or Clutch Pedal Position
(CPP) circuit fault
Electronic shift transmission
- Manual Lever Position
(MLP) sensor out of range
in Park-Transmissions

Does the speed sensor(VSS) have anything to do with the hard shift?
How do I solve code 634
 

Last edited by khaled Alharbi; Oct 17, 2021 at 11:57 AM.
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Old Oct 17, 2021 | 11:57 AM
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I have no idea exactly what you're working on, but if it's an electronically controlled transmission (AOD-E/4R70W or E4OD/4R100) the VSS signal is needed by the transmission, as an input, to determine shift points. But those codes are telling you what you need to know.

You've got a VSS issue that needs attention, and the MLPS needs adjustment, if not replacement.
 
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Old Oct 17, 2021 | 11:59 AM
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Originally Posted by SFaulken
I have no idea exactly what you're working on, but if it's an electronically controlled transmission (AOD-E/4R70W or E4OD/4R100) the VSS signal is needed by the transmission, as an input, to determine shift points. But those codes are telling you what you need to know.

You've got a VSS issue that needs attention, and the MLPS needs adjustment, if not replacement.
How do I change the MLPS, where is it?
 
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Old Oct 18, 2021 | 09:46 AM
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Before you start loading up the parts shotgun, inspect all trans wiring connectors & I'd open the computer & look for leaking capacitors.

Very doubtful your VSS & the MLPS just decided to go out at the same time.

 
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Old Oct 18, 2021 | 11:31 AM
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Originally Posted by Scndsin
Before you start loading up the parts shotgun, inspect all trans wiring connectors & I'd open the computer & look for leaking capacitors.

Very doubtful your VSS & the MLPS just decided to go out at the same time.
Can you explain in a better way? I don't understand my English is not good What does shotgun mean??
 
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Old Oct 18, 2021 | 11:38 AM
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Sorry, no problem. It means to throw parts at a problem without diagnosing. Inspect, clean if necessary & test first.

The connectors, their wires & pins at the transmission & the vss sensor on the rear are subject to abuse.

The capacitors in the computer are past their life expectancy & leak frequently & cause faulty codes.

This computer along with the PSOM behind the speedometer gave multiple random trans codes:



 
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Old Oct 18, 2021 | 11:41 AM
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Originally Posted by Scndsin
Sorry, no problem. It means to throw parts at a problem without diagnosing. Inspect, clean if necessary & test first.

The connectors, their wires & pins at the transmission & the vss sensor on the rear are subject to abuse.
I checked the wires, but I don't see any cut wires. I think it needs cleaning, because it has oil on it or Dust
 
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Old Oct 18, 2021 | 11:47 AM
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The design of the MLPS is problematic & was changed from the connector inserting vertically to horizontal (from the side) because of contamination.

The connector on the passenger side should be behind a metal shield, but frequently has strain & heat damage.

How hard of a life has the truck led?
 
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Old Oct 18, 2021 | 11:50 AM
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As asked above, what trans?
 
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Old Oct 18, 2021 | 11:51 AM
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Originally Posted by Scndsin
The design of the MLPS is problematic & was changed from the connector inserting vertically to horizontal (from the side) because of contamination.
I don't think the problem with mlps It's good to change gears, But the problem is in the kick or hard shift Is the problem with MLPS or VSS?
 
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Old Oct 18, 2021 | 11:53 AM
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Originally Posted by Scndsin
As asked above, what trans?
trans E
axle 19
what does it mean
 
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Old Oct 18, 2021 | 12:21 PM
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You have the bigger, E4OD trans & 8.8 rear.
 
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Old Oct 18, 2021 | 12:30 PM
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Originally Posted by Scndsin
You have the bigger, E4OD trans & 8.8 rear.
thanks . Which number do I put in PSOM?
 
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Old Oct 18, 2021 | 12:38 PM
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Hard shifts are known as limp mode. The computer increases line pressure to make sure shifts happen & things get lubricated. With mine, they came & went for years.
 
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Old Oct 18, 2021 | 12:40 PM
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Originally Posted by Scndsin
Hard shifts are known as limp mode. The computer increases line pressure to make sure shifts happen & things get lubricated. With mine, they came & went for years.
Does he have a solution?
 
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