The cluster has to contain 'matching' information that the PCM vid program block has so there is a match otherwise the PCM won't allow the engine to start. A simple inhibit function.
This is the passive quality of the system and the average person cannot defeat this 'match' . You fell into it not knowing the cluster just can't be changed out like that.
The dealer can do all the programming.
Steve, I don't know the year the diagnostics started but believe it is used in the cars as far back as 99.
Leaving the ignition on times out the PATS if the lamp is flashing rapidly. Timer action.
Then it will code flash one of a 13,14, 15, or 16.
13 is key code not recieved, key not coded or the wrong key.
14 is partial key code recieved. Some kind of interference.
15 is key not programmed.
16 is the faulty link between the PATS and the PCM vid block.
In this case if the DASH id were missing or corrupted, changed you would see a code 16 from pats, possible code P1639 from the PCM and a Hec code of either 9681 or an A139 depending on where the fault is.
These all point to the same kind of trouble and seen from different points in the associated systems.
A pcm P code of 1639 would be the vid block in the PCM faulty and can't ID the PATS signals.
As a side note, a "partial" vid block corrupt can still result is letting the engine start and drive ok but if the tire size and gear ratio info is corrupted the speedometer won't read correct and may even alter the trans shifting sked a small amount. A code P1639 would be stored and the SES lamp would be lighted..
When you look at this from a larger perspective it make perfect sense.
I...have... first hand experience with it. Got into a corrupted vid block situation twice fooling around with a programmer. Live and learn what not to do is the price of progress.
I have a 17 page PATS programming doc.
It shows 5 different versions of PATS from A to E.
The 99-04 F150 has type C with different versions in the Harley and larger trucks.
Page 14 lists all the Fmoco vehs and what system versions they have up to 04.
Hint for all, this info can be 'dug up' off the internet.
Hope this is useful for all those who have a need to know.
Last edited by Bluegrass; 09-21-2006 at 12:40 AM.