View Single Post
Old 01-11-2024, 06:00 PM   #5
Doug Domm
Member
 
Join Date: Apr 2006
Location: canada
Posts: 245
Likes: 26
Liked 83 Times in 20 Posts
Default Re: Alternator problem on 2021 GMC Terrain

My daughters Terrain had an issue of absolute stone cold dead battery when parking overnight in -40 temps due to a parasitic draw that the techs couldn’t track down. It turned out to be the module for the heated seats was sensing the temp and turning them on. Our daughter in laws Acadia was having a voltage regulating issue which turned out to be the ECU. Our neighbor is a tech and has had several issues as you’ve described and each time it was the ECU.
Doug Domm is offline   Reply With Quote