I had the keyless entry removed because it only worked 50% of the time. Now the engine will not crank over and the anti-theft light keeps blinking. Can I disarm/bypass the anti-theft system?

 

Ok, I am going to be reaching pretty far on this one, so it will be pretty cool if it works out.

There was a thread a week or so ago, where someone was having trouble with their 98 f150, and Homer Winzlow produced a diagram that showed a RAP(remote anti-theft personality) circuit.

So, the possibility exists that Ford used the same wiring on the van. Here's what that diagram had.

In what they call the RPO relay block, is a "starter interrrupt relay". It is fed power with a W/P. I thought this would be white/pink, but maybe it's white/purple? Because leaving the relay is a W/PK which also could be white/pink. Anyway, if you can zero in on this relay, there should also be a LG/P wire leaving the relay. This is the wire that goes to the anti-theft module. It looks like if you ground this (lightgreen/purple?), it will acitivate the starter interrupt relay when the key is turned, and let it crank over.

 

I think we need a little clarification on the situation. As I am understanding this, you had a keyless entry and I am assuming it was an aftermarket system? Was this a full alarm system with starter ineterupt? Was the system removed and worked for awhile and not it doesnt work?

Theft light flashing I am asuming you mean the factory PATS system theft lamp. This would indicate that the Pats key is inoperative (often caused by losing the chip out of the key), The Pats transceiver is broken, which could have been caused by splice wiring from the security system, or a PCM power fault, often caused by a defective PCM power relay.

You should get very detailed on the exact situation, when the problem started, who removed the keyless, was it factory or aftermarket, was it just an alarm added to the factory keyless, etc. But the primary fault I am seeing here is a PATS system failure. This can also be something as simple as a near dead battery. But I am just guessing someone pulled out the alarm system and inadvertantly unplugged or loosened the conector to the PATS transciever.

 

Where is the starter interrupt relay and the anti-theft module located? Thanks for your help!

 

I don't know, do you have a bank of relays somewhere under the hood?

All this anti-theft stuff sounds involved, and it's too bad we have to have it on the vehicles nowadays. Homer brought up a lot of points in his post. But I am wondering with all the modules and different gauntlets that have to be passed to make the vehicle start, does it always boil down to that starter interrupt relay? If it does, and if he finds it, he should be able to go around it? Although if it's that simple, you would think the crooks would have it all figured out too?