python 991, pkfm in 1997 expedition

Hello.  First off let me say that I am experienced in installations but I have not done them on a regular basis in a while...so I'm a tad rusty and new products have arisen that I am not entirely familiar with.  Particularly the newer line of DEI's Xpresskits.

I am looking for some help/incite into installing a Python 991 2-way A/RS system with the PKFM Xpresskit into a 1997 Ford Expedition.  I have made all the necessary connections (solder & tape) for the alarm and everything functions properly.  All functions of the remote start work properly as well except for that the PKFM seems to NOT be accepting the programming.  I can insert the key into the cylinder and remote start the vehicle and everything functions properly that way...but programming the bypass is just not working as it is described. 

I followed the install instructions (1-A) for the PKFM and had tried making the connections for the Tx & Rx wires to the vehicle's wiring and the bypass's LED went solid, which would indicate the wires are backwards.  I switched the wires and the same results arose.  Which was really weird because any literature I've found on this unit would indicate that the unit's LED would flash rapidly if this were so.  Also to note, is that upon testing the 4 vehicle's wires coming out of the PATS receiver, none of them have any positive voltage to be read so I know which wire to attach the PKFM's orange ignition input wire to. 

Maybe I am missing something small or overlooked something, but I have double checked my work.

Has anyone had any experience with this particular unit...or perhaps has any wire colors for the vehicle's PATS system so I have DEFINITIVE wire colors to attach to.  Any and all help would be greatly appreciated.  Thank you in advance.

Here is a link to Fortins' install guide :  https://ifar.ca/download/393/key-override-all_ford_expedition_(1997-2001).rev-a.pdfIt has a picture of the PATS connector and pin numbers / description.  Could not find a listing for your truck at iDatalinkto get the wire colors.  They start in 1999 with this info :  Expedition 99-02   TX - Pin4 WHITE/ LtGreen    RX - Pin3 Gray/OrangeSoldering is fun!

it so happens that i did the exact vehicle a couple of weeks ago and i had the same problem the pkfm didnt program at all . i tried for hours but no success i finally used a key in a box to remote start the vehicle,i even called my friends at my dei outlet but they could'nt explain it also.the strange thing thing wes that the ignition wire in the pats connector would only read only for a second and only when the ignition switch was turned on and off,like i said i finally gave up and used a key in a 556u.hope this helps good lucktriniforever

kreg357 wrote: Here is a link to Fortins' install guide :  https://ifar.ca/download/393/key-override-all_ford_expedition_(1997-2001).rev-a.pdf It has a picture of the PATS connector and pin numbers / description.  Could not find a listing for your truck at iDatalink to get the wire colors.  They start in 1999 with this info :  Expedition 99-02   TX - Pin4 WHITE/ LtGreen    RX - Pin3 Gray/Orange

Yea the instructions for the PKFM had the same pictures of the PATS connector...as well as for all the newer styles of PATS connectors.  And it said what each wires function was, but we know that car manufactureres like to switch things around whenever they feel like it.  Thanks for the link though. I appreciate it.

triniforever wrote: it so happens that i did the exact vehicle a couple of weeks ago and i had the same problem the pkfm didnt program at all . i tried for hours but no success i finally used a key in a box to remote start the vehicle,i even called my friends at my dei outlet but they could'nt explain it also.the strange thing thing wes that the ignition wire in the pats connector would only read only for a second and only when the ignition switch was turned on and off,like i said i finally gave up and used a key in a 556u.hope this helps good luck

I ran into the same thing while doing this vehicle.  The supposed ignition wire that was labeled in the instructions was located in the 4 pin harness (which looks NOTHING like it does in the instructions compared to the truck's actual connector) was tested and I got a small, quick spike of positive voltage when I turned the key to ignition.  It didn't even hit 1V+ then dropped to 0V+.  It tested more like 0.888V+ then dropped to nothing.

I am trying to avoid sacrificing a key to a 556U for this because the owner currently only has 1 programmed key for it and doesn't want to spend the $50 on another key just to NOT use it at all...which is understandable. 

I have a 555F that I could use as well for this...but unfortunately that requires 2 keys for programming...and is a bit tricky to get to stay EXACTLY where you need it to stay sometimes.  I've used them plenty of times and as soon as I put the steering column shroud back in place and screw it down...the key pellet moves and the remote starter doesn't work...so I have to take it off AGAIN to reposition it and risk it happening AGAIN.  LOL  Many installers would probably be able to sympathize with me on this one.  I've ran into the same issue with the 556U's on occasion as well because the antenna ring provided with the 556U takes up space around the key cylinder and sometimes makes it a tad tricky to keep positioned properly for operation.

I am simply trying to avoid killing a key, so to speak, for this install to try to keep the customer happy.  But we all know that MIGHT not be possible. :)

Re-Flash the PKFM to use FIRMARE 3 instead. Then try programming the module as instructed. I know this sounds odd but I just had a very similiar experience today with a Mercury Grand Marquis and called DEI and the guy I talked to said to do this. Also try going wire to wire instaed of data to data. They are having alot of problems with the D2D side of the units right now.