New key to start in the ignition?

2000 VOLKSWAGEN GOLF
15,000 MILES • 1.9L • TURBO • MANUAL
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AOIFEKILROY
  • MEMBER
  • 1 POST
If a mechanic changes the brain in the car will it need a. New key to start in the ignition .. Just someone wired something wrong in the car and now it will on start on easy start pumps been changed brain been changed and timing belt and car wont start and turn key?
Nov 10, 2014 at 11:36 PM
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SQM
  • ✓Experienced Mechanic
  • 6,383 POSTS
Hello,

Just to clarify, the ECM was replaced.
Keep in mind that any time any of those modules get replaced, it will need to be programmed to your vehicle.
Without the relearning process the new module will not work.

https://www.2carpros.com/articles/how-a-car-computer-works-pcm-ecm-bcm

For this Golf it will need a VW specific scan tool to perform the programming.
I have attached the programming procedure below.

Please let me know of any questions.
Thank you.
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Oct 3, 2021 at 3:58 AM
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