Notices
1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

PSOM Reprogram Mileage Reading

Thread Tools
 
Search this Thread
 
Old Oct 1, 2017 | 06:08 PM
  #1  
TexasGuy001's Avatar
TexasGuy001
Thread Starter
|
Hotshot
20 Year Member
Photogenic
Photoriffic
Liked
Joined: Sep 2001
Posts: 11,958
Likes: 228
Question PSOM Reprogram Mileage Reading

I've seen the information about recalibrating the PSOM for tire size etc. Does anyone have the information on how to reprogram the actual mileage reading? I have a different one that I'd like to use, but would like to program the actual mileage, so that it matches the truck.
 
Reply
Old Oct 1, 2017 | 06:34 PM
  #2  
PRIMERED79 SHORT BED's Avatar
PRIMERED79 SHORT BED
Laughing Gas
10 Year Member
Liked
Loved
Community Favorite
Joined: Jan 2012
Posts: 1,106
Likes: 25
Subscribe.
 
Reply
Old Oct 1, 2017 | 07:20 PM
  #3  
Diesel_Brad's Avatar
Diesel_Brad
Fleet Owner
15 Year Member
Photogenic
Liked
Loved
Joined: May 2009
Posts: 21,437
Likes: 76
From: Gilbert, PA
I am pretty sure that is Not a viable option. If it was you could simply reset your 399,999 cluster to 40,000 and lie about the milage on the truck
 
Reply
Old Oct 1, 2017 | 08:03 PM
  #4  
PRIMERED79 SHORT BED's Avatar
PRIMERED79 SHORT BED
Laughing Gas
10 Year Member
Liked
Loved
Community Favorite
Joined: Jan 2012
Posts: 1,106
Likes: 25
Is there a way we can have it sent off to have it done?
 
Reply
Old Oct 1, 2017 | 08:09 PM
  #5  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 301
From: Easton,Ks
Anybody with a EPROM burner can just copy the mileage from one board to the other boards EEPROM chip. It is not rocket science.
Or you can buy a eprom burner off of ebay and do it yourself.
Or you can un-solder the EEPROM and solder it into the other board with or without a soldered socket.
 
Reply
Old Oct 1, 2017 | 08:31 PM
  #6  
PRIMERED79 SHORT BED's Avatar
PRIMERED79 SHORT BED
Laughing Gas
10 Year Member
Liked
Loved
Community Favorite
Joined: Jan 2012
Posts: 1,106
Likes: 25
Originally Posted by subford
Anybody with a EPROM burner can just copy the mileage from one board to the other boards EEPROM chip. It is not rocket science.
Or you can buy a eprom burner off of ebay and do it yourself.
Or you can un-solder the EEPROM and solder it into the other board with or without a soldered socket.
I'm not familiar with eproms, so which part do we un-solder?
 
Reply
Old Oct 1, 2017 | 09:26 PM
  #7  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 301
From: Easton,Ks
You might want to read through these links:
https://www.ford-trucks.com/forums/1...r-display.html

https://www.ford-trucks.com/forums/1...splay-fix.html

The red square is the EEPROM chip.
Name:  sKfqbGi.jpg
Views: 4446
Size:  108.1 KB

/
 
Reply
Old Oct 1, 2017 | 11:05 PM
  #8  
PRIMERED79 SHORT BED's Avatar
PRIMERED79 SHORT BED
Laughing Gas
10 Year Member
Liked
Loved
Community Favorite
Joined: Jan 2012
Posts: 1,106
Likes: 25
Subford.
I just swapped in a 93 lightning 120mph speedo into my 92 f150 90mph.
Is it still possible to swap the 92 eeprom chip into the lightning psom and it still work correctly and keep my org mileage?
The threads mention the eeprom keeping the mileage and gear ratio, i just want to make sure the speedo isn't affected.
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-1

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-2

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-3

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-4

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-5

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-6

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
story-7

10 Most Surprising 2026 Ford Truck Features!

 Joe Kucinski
story-8

Top 10 Ford Trucks Coming to Mecum Indy 2026

 Brett Foote
story-9

5 Best / 5 Worst Ford Truck Wheels of All Time

 Joe Kucinski
Old Oct 2, 2017 | 06:59 AM
  #9  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 301
From: Easton,Ks
I think the program in the large chip is what decides on how far to drive the needle. But this is just a guess. The EEPROM chip is just an information storage device for when the power is off.
 
Reply
Old Oct 2, 2017 | 04:33 PM
  #10  
Eddiec1564's Avatar
Eddiec1564
Cargo Master
15 Year Member
Joined: Mar 2007
Posts: 2,935
Likes: 34
From: Arcadia, Fla
Originally Posted by subford
I think the program in the large chip is what decides on how far to drive the needle. But this is just a guess. The EEPROM chip is just an information storage device for when the power is off.
The EEPROM does have needle movement data stored in it for upper scale and lower scale needle calibration. I found out about that after a EEPROM swap on my E350 Bus. Had to copy only the milage data over to the other EEPROM along with the pinion ratio factor too, left all other data same for that speedometer.

As for resetting mileage to a specific number, I have not figured out the data encoding parity, so no go(yet)on changing mileage beyond swapping data sets around.
 
Reply
Old Oct 2, 2017 | 08:37 PM
  #11  
TexasGuy001's Avatar
TexasGuy001
Thread Starter
|
Hotshot
20 Year Member
Photogenic
Photoriffic
Liked
Joined: Sep 2001
Posts: 11,958
Likes: 228
I would have thought that Ford dealers would have had a way to do this, if this part had to be replaced when the trucks were fairly new.
 
Reply
Old Oct 2, 2017 | 08:47 PM
  #12  
PRIMERED79 SHORT BED's Avatar
PRIMERED79 SHORT BED
Laughing Gas
10 Year Member
Liked
Loved
Community Favorite
Joined: Jan 2012
Posts: 1,106
Likes: 25
Whats this all about?
 
Reply
Old Oct 2, 2017 | 10:51 PM
  #13  
TexasGuy001's Avatar
TexasGuy001
Thread Starter
|
Hotshot
20 Year Member
Photogenic
Photoriffic
Liked
Joined: Sep 2001
Posts: 11,958
Likes: 228
It looks like he is sending a false signal so it thinks its being driven. That would work to add miles but not take them off. It would take a while to have it come back around and up to the correct mileage doing that. From what I understand it rolls over to zero again after 400k.
 
Reply
Old Oct 2, 2017 | 10:52 PM
  #14  
TexasGuy001's Avatar
TexasGuy001
Thread Starter
|
Hotshot
20 Year Member
Photogenic
Photoriffic
Liked
Joined: Sep 2001
Posts: 11,958
Likes: 228
The idea of swapping the EEPROM has me worried I'll damage the parts I'm working with. I've never used a burner for them, but am curious to see how that works.
 
Reply
Old Oct 2, 2017 | 10:54 PM
  #15  
TexasGuy001's Avatar
TexasGuy001
Thread Starter
|
Hotshot
20 Year Member
Photogenic
Photoriffic
Liked
Joined: Sep 2001
Posts: 11,958
Likes: 228
Originally Posted by PRIMERED79 SHORT BED
Subford.
I just swapped in a 93 lightning 120mph speedo into my 92 f150 90mph.
Is it still possible to swap the 92 eeprom chip into the lightning psom and it still work correctly and keep my org mileage?
The threads mention the eeprom keeping the mileage and gear ratio, i just want to make sure the speedo isn't affected.
I'm also swapping to a Lightning speedometer.
 
Reply



All times are GMT -5. The time now is 12:50 AM.

story-0
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-1
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-2
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-3
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-4
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-5
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-6
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-7
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-8
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-9
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE