Security light flashing?

Tiny
GERALDLOVETT
  • MEMBER
  • 2000 FORD F-150
  • 5.4L
  • V8
  • 2WD
  • AUTOMATIC
  • 105,000 MILES
Mechanic just got me for almost $800.00 for a new computer. I drove off the lot and didn't even make it home. I was going down the road and the engine just shut off. I pulled in a parking lot and tried to read crank it. On regular attempts it seems like I was going to get a crank out of it I see the def light is flashing on the dash.
Thursday, January 9th, 2020 AT 6:20 PM

3 Replies

Tiny
BMDOUBLE
  • MECHANIC
  • 1,139 POSTS
When your truck is not starting, try and swap the PCM relay with another relay that looks like it or just replace it if it is original. I've fixed lots of these trucks with the same scenario of other shops replacing the PCM and the vehicle still doesn't start! PCM relay has been the fix for at least 90% of the ones that I've had this issue with.
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Saturday, January 16th, 2021 AT 11:13 AM
Tiny
PATRLCIA PERKINS
  • MEMBER
  • 1 POST
  • 1999 FORD F-150
  • 1.0L
  • V6
  • 2WD
  • MANUAL
  • 140,000 MILES
Theft light flash how to turn it off?
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Monday, June 28th, 2021 AT 2:26 PM (Merged)
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 43,110 POSTS
If you have the remote close and lock the doors and leave the truck for thirty minutes and then unlock. Here is a guide that will help was well:

https://www.2carpros.com/articles/how-to-reset-a-security-system

Please run down this guide and report back.

Cheers, Ken
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Monday, June 28th, 2021 AT 2:26 PM (Merged)

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