Theft light keeps coming on preventing the car from starting?

Tiny
KUTECHT23
  • MEMBER
  • 2002 LINCOLN NAVIGATOR
  • 5.4L
  • V8
  • 4WD
  • AUTOMATIC
  • 147,000 MILES
I have replaced the PCM relay, The battery and got a new key programmed. The car has stalled while driving, resetting the battery only works sometimes. I haven't gotten any codes except for a few for ABS. What could be my problem?
Thursday, May 15th, 2025 AT 12:16 PM

1 Reply

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 51,648 POSTS
Yep, I have seen the central security module go out and cause this problem. When you did the scan did you use a CAN scanner? this should help us confirm the failure here is a video to watch to see how the scan is done:

https://youtu.be/u-4syLc-ifQ

Here is the location of the module, I would try unplugging it and then plugging it in again to see if there is a bad connection or corrosion and the connector. Check out the images (below). Let us know how it goes.

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Friday, May 16th, 2025 AT 11:28 AM

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