I want to remove the non-functioning Ford unit from my wife's Expedition (2003). This seems like a dumb question, but do you need or can you remove the Ford unit when replacing with aftermarket? Maybe this is an obvious answer but I've never installed an alarm before. I have plenty of experience tapping wires and other electrical experience so I am pretty sure this is something I can tackle in a full day. It also appears that I will need a PKALL module for the remote starter function as well.

I'm eyeballing a Viper 5901 on Amazon for about $208. Looking at others on here who run one, it seems like a decent unit. Any other advice? I have the factory service manual for diagrams but if there is a place to get a condensed list and location of what to do that would be helpful.

Wow - been a member since 2005 basically trolling for info and now I'm finally posting...

Thanks in advance.

 

I have a viper alarm that I had Best Buy install. Not sure what they did before installing it. I had no factory alarm, just that anti-theft light that kept flashing. It. still flashes when my viper is alarmed.

 

Deffinitly need a PKALL. It should be fine to leave the Ford in there. The viper will disarm it if need be. In my experience, most factory "alarm" systems dont really do much of anything to prevent theft.

As for your diagram, check out www.the12volt.com

Pre warning, the locks on these trucks can be tricky, and many have to be diode isolated. you have the newer generation Expy being an '03, so it may be different for that year. I never did an alarm in that body style, only decks.

 

Clarification question on my part.

When you say "non-functioning Ford unit " what unit are you talking about ?

Is this the factory RKE or are you talking the Ford Gold VSS ( The code Alarm that Ford OEMs ) ?

From the factory the truck only has the RKE and the immobilizer, if a VSS was added, the dealer did it.

 

Must be the VSS then. Thanks for the help!