Larger tires affecting speedometer

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Apr 23, 2014 | 09:44 PM

#16

RIKIL

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Quote:

Originally Posted by White Mountain Goat

^Thats the method I've tried every time with no luck. I will look it over and see if any wires have been spliced together.

As was mentioned before, there is a finite number of times it can be changed. If you REALLY want to change it there is a place on line that will sell you a reman PSOM that will have this limit reset. You'll tell them your mileage and they'll program that for you and send you the PSOM. probably not worth it though, I think it's a couple hundred bucks.

What also might help is you can take a video of what you're doing and post to YouTube so we can see if you're missing a step or something.

Apr 24, 2014 | 07:14 AM

#17

subford

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From: Easton,Ks

Quote:

Originally Posted by White Mountain Goat

I will look it over and see if any wires have been spliced together.

Note if the mileage is up-dating after each drive of the truck then the PSOM is up-dating the EEPROM and you do not have the wiring problem.

Apr 24, 2014 | 07:26 AM

#18

subford

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From: Easton,Ks

Quote:

Originally Posted by RIKIL

there is a place on line that will sell you a reman PSOM

How can you rebuild a PSOM other than change the caps?

Quote:

Originally Posted by RIKIL

You'll tell them your mileage and they'll program that for you and send you the PSOM.

I would like to see what math they used to do that.

Apr 24, 2014 | 09:48 AM

#19

RIKIL

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Quote:

Originally Posted by subford

How can you rebuild a PSOM other than change the caps?

Making sure things don't fall off is a good start, this was my issue back a few years ago...

https://www.ford-trucks.com/forums/7...ml#post6657625

Quote:

Originally Posted by subford

I would like to see what math they used to do that.

No idea, you would need to ask them. I do remember on the site I found (years ago) that if I had to buy a new PSOM where I told them what mileage to program, they required a document to be signed stating that was the true mileage of the vehicle.

Apr 24, 2014 | 11:01 AM

#20

Crewcabber

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From: Lynnwood Wa.

I vote STICKY for this topic. ......

Apr 24, 2014 | 11:58 AM

#21

White Mountain Goat

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Quote:

Originally Posted by subford

Note if the mileage is up-dating after each drive of the truck then the PSOM is up-dating the EEPROM and you do not have the wiring problem.

The odometer is working, I assume that is what you mean.

Apr 24, 2014 | 12:00 PM

#22

subford

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From: Easton,Ks

Yes the odometer.

May 4, 2014 | 07:02 PM

#23

White Mountain Goat

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Just wanted to update this thread. I went out to try one more time to recalibrate the speedometer. I tried grounding the PSOM to several points around the cab that I felt sure would give a good ground, no luck any time. Finally I stuck the wire behind a screw that is holding the door panel on, a last resort before giving up really. Well, it worked!

Thanks to all who helped, and provided the link to reprogramming.