ECU hard reset and clear?

Tiny
CRYBABYCHRISHON
  • MEMBER
  • 2020 BUICK ENCORE
  • 1.4L
  • 4 CYL
  • 4WD
  • AUTOMATIC
  • 151,189 MILES
How do I hardreset and clear thee check engine light?
Friday, April 24th, 2026 AT 11:23 AM

1 Reply

Tiny
STEVE W.
  • MECHANIC
  • 15,702 POSTS
Disconnecting the battery on any GM newer than 2016-2018 (depends on model) will not erase the codes. To erase them requires a higher level scan tool. Then you need to put the vehicle in accessory mode and clear the codes, turn it off. Wait about 5 seconds and start it. That process clears the current, pending and history codes, however it will not clear any permanent codes. The PCM has to do that after it sees a set number of drive cycles without the fault returning.
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Friday, April 24th, 2026 AT 7:56 PM

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