Security light flashing?

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

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

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)

KEN L

MASTER CERTIFIED MECHANIC
54,364 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)